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This page is the main reviewer-facing queue: if a PR is ready for review, it belongs here. The triage page contains additional triage-oriented views, but it is not the primary review queue.
This page contains tables of
| Number |
Author |
Title |
Description |
Labels |
+/- |
Modified files (first 100) |
📝 |
💬 |
All users who commented or reviewed |
Assignee(s) |
Updated |
Last status change |
total time in review |
| 34952 |
joneugster author:joneugster |
feat(scripts/autolabel): use `Cli` and integrate `curl` call into `autolabel` |
- use `Cli` for `lake exe autolabel`
- add arguments `--pr xxx --gh` and `--pr xxx --curl ` to chose between different interaction methods with github
- add `--force` to skip the check whether labels are already present. (note: the current `curl` setup doesn't perform this step and neither does the refactor, so I added a `Todo` to remember this. )
- make CI-workflow simpler and more robust by removing current stdout-parsing of the debug-messages which `autolabel` emits.
### Testing
Make some local changes and commit them. Ensure your local `origin/master` is in sync with `upstream/master` if you are on a fork.
- `lake exe autolabel`: prints the labels which would be applicable
- `lake exe autolabel --pr 34952 --gh --force` adds these labels to this PR using `gh`.
- `lake exe autolabel --pr 34952 --gh` adds these labels to this PR using `gh` if no topic labels are present.
- `lake exe autolabel --pr 34952 --curl ` adds these labels to this PR using `curl`. This requires a github access token for authentication
---
[](https://gitpod.io/from-referrer/)
|
CI |
85/72 |
.github/workflows/add_label_from_diff.yaml,scripts/autolabel.lean |
2 |
4 |
['github-actions', 'mathlib-merge-conflicts'] |
nobody |
78-2536 2 months ago |
61-49545 61 days ago |
94-3752 94 days |
| 37865 |
Jun2M author:Jun2M |
feat(Combinatorics/Graph): Edge cut of `Graph` |
This PR introduces
- `edgeCut`: A function on set of vertices that returns the set of edges with exactly one end in the set.
- `IsEdgeCut`: A predicate for set of edges that promises it is `edgeCut` of some set.
- `IsBridge`: An edge `e` is a bridge iff it is a singleton edge cut.
- `IsBond`: An edge Set `B` is bond iff it is minimal nonempty edge cut.
---
- [x] depends on: #35879
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
194/0 |
Mathlib/Combinatorics/Graph/Connected/EdgeCut.Lean,Mathlib/Combinatorics/Graph/Subgraph.lean |
2 |
2 |
['github-actions', 'mathlib-dependent-issues'] |
nobody |
44-20420 1 month ago |
44-38077 44 days ago |
44-38284 44 days |
| 37420 |
artie2000 author:artie2000 |
refactor: change definitions to avoid `ConvexCone` |
Change the definitions of `PointedCone.positive` and `PointedCone.closure` to avoid mentioning `ConvexCone`.
This PR is part of a series deprecating `ConvexCone`: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Replacing.20.60ConvexCone.60.20with.20.60PointedCone.60/with/582738985
---
[](https://gitpod.io/from-referrer/)
|
t-convex-geometry
maintainer-merge
|
10/4 |
Mathlib/Analysis/Convex/Cone/Closure.lean,Mathlib/Geometry/Convex/Cone/Pointed.lean |
2 |
3 |
['YaelDillies', 'github-actions', 'mathlib-merge-conflicts', 'ooovi', 'vihdzp'] |
nobody |
43-49989 1 month ago |
43-49953 43 days ago |
58-70285 58 days |
| 38185 |
Jun2M author:Jun2M |
feat(Order/Partition): operations over Frame |
This PR introduces:
* `Partition.induce`: The induce of a partition by a frame element.
* `Partition.disjUnion`: The disjoint union of two partitions.
* `Partition.bind`: The finer partition obtained by family of partitions for each part of the original partition.
Co-authored-by: Peter Nelson
---
[](https://gitpod.io/from-referrer/)
|
t-order |
89/11 |
Mathlib/Order/Partition/Basic.lean,Mathlib/Order/SupIndep.lean |
2 |
1 |
['github-actions'] |
nobody |
42-16755 1 month ago |
42-16827 42 days ago |
42-16596 42 days |
| 38356 |
SnirBroshi author:SnirBroshi |
feat(Order/ConditionallyCompleteLattice/Finset): `sSup s ≠ ⊤` in a `CompleteLinearOrder` for a finite set without `⊤` |
---
btw `to_dual` here is blocked on #35213
[](https://gitpod.io/from-referrer/)
|
t-order |
20/0 |
Mathlib/Order/ConditionallyCompleteLattice/Finset.lean |
1 |
1 |
['github-actions'] |
nobody |
37-86013 1 month ago |
37-86088 37 days ago |
37-85857 37 days |
| 38325 |
Jun2M author:Jun2M |
feat(Combinatorics/Graph): EndPoint function |
This PR introduces `endPoints`: `Set` of incident vertices, given an edge (in the case of non-edge, return empty).
**Import change**: `Graph/Basic` now imports `Data/Set/Card` to allow reasoning about card of `endPoints`.
[Relavent Zulip thread](https://leanprover.zulipchat.com/#narrow/channel/513188-CSLib/topic/New.20graph.20definitions/with/588616269)
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
large-import
|
83/3 |
Mathlib/Combinatorics/Graph/Basic.lean |
1 |
9 |
['Jun2M', 'SnirBroshi', 'eric-wieser', 'github-actions', 'mathlib-bors'] |
nobody |
37-6611 1 month ago |
37-15441 37 days ago |
38-71553 38 days |
| 38498 |
SnirBroshi author:SnirBroshi |
feat(Order/RelIso/Basic): lift a function to an order morphism into `Relation.Map` or from `Function.onFun` |
For an `α`-relation `r` we have:
```
mapRelHom (f : α → β) : r →r Relation.Map r f f
mapRelEmbedding (f : α ↪ β) : r ↪r Relation.Map r f f
mapRelIso (f : α ≃ β) : r ≃r Relation.Map r f f
```
For a `β`-relation `r` we have:
```
onFunRelHom (f : α → β) : r.onFun f →r r
onFunRelEmbedding (f : α ↪ β) : r.onFun f ↪r r
onFunRelIso (f : α ≃ β) : r.onFun f ≃r r
```
---
These are pretty similar to `SimpleGraph.{Embedding/Iso}.map` and `SimpleGraph.{Hom/Embedding/Iso}.comap`, as [`comap`](https://github.com/leanprover-community/mathlib4/blob/9268b22206b0425419498769f780a91dee03bcf3/Mathlib/Combinatorics/SimpleGraph/Maps.lean#L117-L118) on graphs is a wrapper around `onFun`, and [`map`](https://github.com/leanprover-community/mathlib4/blob/9268b22206b0425419498769f780a91dee03bcf3/Mathlib/Combinatorics/SimpleGraph/Maps.lean#L57-L58) on graphs is *almost* a wrapper around `Relation.Map`.
btw `@[simps]` is angry at me when I try to use it on the structures that use spread syntax.
[](https://gitpod.io/from-referrer/)
|
t-order |
42/0 |
Mathlib/Order/RelIso/Basic.lean |
1 |
1 |
['github-actions'] |
nobody |
34-76655 1 month ago |
34-76730 34 days ago |
34-76499 34 days |
| 38344 |
robo7179 author:robo7179 |
feat(SimpleGraph/Coloring/VertexColoring): Matching is 2 colorable |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
51/0 |
Mathlib/Combinatorics/SimpleGraph/Coloring/VertexColoring.lean |
1 |
5 |
['SnirBroshi', 'github-actions', 'vlad902'] |
nobody |
34-52578 1 month ago |
38-20122 38 days ago |
38-20277 38 days |
| 38222 |
IvanRenison author:IvanRenison |
feat(Combinatorics/SimpleGraph/Girth): add lemmas about isomorphism and girth |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
19/1 |
Mathlib/Combinatorics/SimpleGraph/Girth.lean |
1 |
6 |
['IvanRenison', 'SnirBroshi', 'github-actions', 'vlad902'] |
nobody |
34-36200 1 month ago |
41-11113 41 days ago |
41-10882 41 days |
| 38528 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Paths): some cycle lemmas are true for circuits |
Add `IsCircuit.{not_of_nil,ne_bot,three_le_length}` by using their corresponding `IsCycle` proofs.
Also golfs a bit.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
17/9 |
Mathlib/Combinatorics/SimpleGraph/Paths.lean |
1 |
1 |
['github-actions'] |
nobody |
34-35104 1 month ago |
34-35174 34 days ago |
34-34943 34 days |
| 38549 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Copy): `Is(Ind)Contained` `completeGraph` lemmas |
- `G ⊑ completeGraph V`
- `G ⊑ completeGraph W ↔ Nonempty (V ↪ W)`
- `completeGraph V ⊴ completeGraph W ↔ Nonempty (V ↪ W)`
- `G ⊴ completeGraph W → G = ⊤`
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
12/0 |
Mathlib/Combinatorics/SimpleGraph/Copy.lean |
1 |
1 |
['github-actions'] |
nobody |
33-41679 1 month ago |
33-41748 33 days ago |
33-41517 33 days |
| 38529 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Girth): `egirth ⊤ = 3` when there are at least 3 vertices |
Since `Nontrivial` is not enough, we use the condition `3 ≤ ENat.card α`.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
17/0 |
Mathlib/Combinatorics/SimpleGraph/Girth.lean |
1 |
5 |
['SnirBroshi', 'github-actions', 'vlad902'] |
nobody |
33-41622 1 month ago |
34-32339 34 days ago |
34-32108 34 days |
| 37835 |
YaelDillies author:YaelDillies |
doc(Algebra/Order): update mentions of `OrderedSemiring` and friends |
As of #20676, it was replaced by `IsOrderedRing`.
Not all docs were straightforward to update.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-order
label:t-algebra$ |
123/280 |
Counterexamples/HomogeneousPrimeNotPrime.lean,Counterexamples/OrderedCancelAddCommMonoidWithBounds.lean,Mathlib/Algebra/Group/Subgroup/Order.lean,Mathlib/Algebra/Group/ULift.lean,Mathlib/Algebra/Order/AddTorsor.lean,Mathlib/Algebra/Order/Floor/Defs.lean,Mathlib/Algebra/Order/Floor/Ring.lean,Mathlib/Algebra/Order/Floor/Semiring.lean,Mathlib/Algebra/Order/Group/Cone.lean,Mathlib/Algebra/Order/Group/Cyclic.lean,Mathlib/Algebra/Order/GroupWithZero/Unbundled/Defs.lean,Mathlib/Algebra/Order/Hom/Monoid.lean,Mathlib/Algebra/Order/Interval/Set/Monoid.lean,Mathlib/Algebra/Order/Monoid/Canonical/Defs.lean,Mathlib/Algebra/Order/Monoid/Unbundled/Defs.lean,Mathlib/Algebra/Order/Monoid/Unbundled/ExistsOfLE.lean,Mathlib/Algebra/Order/Positive/Ring.lean,Mathlib/Algebra/Order/Ring/Basic.lean,Mathlib/Algebra/Order/Ring/Defs.lean,Mathlib/Algebra/Order/Ring/Unbundled/Basic.lean,Mathlib/Algebra/Order/Star/Basic.lean,Mathlib/Algebra/Order/Sub/WithTop.lean,Mathlib/Algebra/Order/ToIntervalMod.lean,Mathlib/Algebra/Order/WithTop/Untop0.lean,Mathlib/Combinatorics/Pigeonhole.lean,Mathlib/Data/Finsupp/Weight.lean,Mathlib/Data/NNReal/Defs.lean,Mathlib/Data/Nat/Cast/Order/Basic.lean,Mathlib/Data/Nat/Cast/Order/Ring.lean,Mathlib/MeasureTheory/Function/LpOrder.lean,Mathlib/MeasureTheory/Measure/Typeclasses/Finite.lean,Mathlib/Order/Filter/Germ/OrderedMonoid.lean,Mathlib/RingTheory/GradedAlgebra/Radical.lean,Mathlib/RingTheory/HahnSeries/PowerSeries.lean,Mathlib/RingTheory/HahnSeries/Valuation.lean,Mathlib/RingTheory/MvPolynomial/WeightedHomogeneous.lean,Mathlib/Tactic/NormNum/Ineq.lean |
37 |
9 |
['NoahW314', 'SnirBroshi', 'github-actions', 'mathlib-merge-conflicts'] |
nobody |
33-33558 1 month ago |
33-33583 33 days ago |
48-28486 48 days |
| 38554 |
YaelDillies author:YaelDillies |
chore(Combinatorics/SimpleGraph): use the auto-param in `loopless` more |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
5/13 |
Mathlib/Combinatorics/Digraph/Orientation.lean,Mathlib/Combinatorics/SimpleGraph/AdjMatrix.lean,Mathlib/Combinatorics/SimpleGraph/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Hasse.lean,Mathlib/Combinatorics/SimpleGraph/Maps.lean,Mathlib/Combinatorics/SimpleGraph/Prod.lean,Mathlib/Combinatorics/SimpleGraph/Regularity/Uniform.lean,Mathlib/Order/Cover.lean |
8 |
6 |
['SnirBroshi', 'YaelDillies', 'github-actions'] |
nobody |
32-22178 1 month ago |
32-54519 32 days ago |
32-56357 32 days |
| 38364 |
openendings author:openendings |
feat: create Order/DirectedCompletePartialOrder/Defs.lean |
Define DirectedCompletePartialOrder and its interaction with iSup and sSup.
---
A DirectedCompletePartialOrder is equivalently:
- a partial order with LUBs of nonempty directed sets;
- what happens when you remove ⊥ from a CompletePartialOrder; or
- a ConditionallyCompletePartialOrder in which every directed set is BddAbove.
Like CPOs, DCPOs are commonly studied in denotational semantics.
Potential applications:
- [#Is there code for X? > Summing `ENat`s without topology](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Summing.20.60ENat.60s.20without.20topology/with/590070848) -- defining infinite sums in an DCPO-enriched `AddCommMonoidWithTop` such as `ENat` or `ENNReal`.
- [#Is there code for X? > Scott Induction](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Scott.20Induction/with/590112858) -- fixpoint theorems similar to `OmegaCompletePartialOrder`, generalised to arbitrary cardinalities.
[](https://gitpod.io/from-referrer/)
|
t-order
new-contributor
|
123/0 |
Mathlib.lean,Mathlib/Order/DirectedCompletePartialOrder/Defs.lean,docs/references.bib |
3 |
4 |
['SnirBroshi', 'github-actions', 'openendings'] |
nobody |
31-10434 1 month ago |
37-554 37 days ago |
37-61549 37 days |
| 38612 |
SnirBroshi author:SnirBroshi |
feat(Order/SuccPred/CompleteLinearOrder): `sSup s < x` iff theorems when we know if `x` is a successor pre-limit or not |
Adds the following theorems (along with their duals and indexed versions):
```lean
sSup_lt_iff_of_not_isSuccPrelimit : ¬IsSuccPrelimit x → sSup s < x ↔ ∀ a ∈ s, a < x
le_sSup_iff_of_not_isSuccPrelimit : ¬IsSuccPrelimit x → x ≤ sSup s ↔ ∃ a ∈ s, x ≤ a
Order.IsSuccPrelimit.sSup_lt_iff : IsSuccPrelimit x → sSup s < x ↔ ∃ a < x, ∀ b ∈ s, b < a
Order.IsSuccPrelimit.le_sSup_iff : IsSuccPrelimit x → x ≤ sSup s ↔ ∀ a < x, ∃ b ∈ s, a ≤ b
```
They are similar to these existing theorems, but not the same:
```lean
sSup_lt_iff : sSup s < x ↔ ∃ a < x, ∀ b ∈ s, b ≤ a
le_sSup_iff_forall_lt : x ≤ sSup s ↔ ∀ a < x, ∃ b ∈ s, a < b
```
---
[](https://gitpod.io/from-referrer/)
|
t-order |
43/0 |
Mathlib/Order/SuccPred/CompleteLinearOrder.lean |
1 |
6 |
['SnirBroshi', 'github-actions', 'vihdzp'] |
nobody |
30-67643 1 month ago |
31-64557 31 days ago |
31-64326 31 days |
| 37930 |
vlad902 author:vlad902 |
chore(SimpleGraph): move `cycleGraph` to its own file |
PR #34797 re-defined `cycleGraph` independent of `circulantGraph`. Now move the definition of `cycleGraph` to its own file so that the definition can be used without importing the algebra hierarchy.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
173/148 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Circulant.lean,Mathlib/Combinatorics/SimpleGraph/Cycle.lean |
3 |
2 |
['github-actions', 'mathlib-merge-conflicts'] |
nobody |
29-71612 29 days ago |
29-71635 29 days ago |
29-71791 29 days |
| 38747 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Basic): more `neighborSet` and `IsIsolated` lemmas |
---
`neighborSet_mono` moved from `Maps.lean` to `Basic.lean` with a simpler proof
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
72/17 |
Mathlib/Combinatorics/SimpleGraph/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Finite.lean,Mathlib/Combinatorics/SimpleGraph/Maps.lean,Mathlib/Combinatorics/SimpleGraph/StronglyRegular.lean |
4 |
2 |
['github-actions', 'vlad902'] |
nobody |
29-6891 29 days ago |
29-13847 29 days ago |
29-67905 29 days |
| 38841 |
SnirBroshi author:SnirBroshi |
feat(Mathlib/Order/SuccPred/Limit): more `WithTop` lemmas about `IsMin`/`CovBy`/`IsSuccLimit` |
---
Continues the work from #38244
We should probably also have such lemmas for `WithTopBot`/`WithBotTop`, but that's for another day
[](https://gitpod.io/from-referrer/)
|
t-order |
111/30 |
Mathlib/Order/Cover.lean,Mathlib/Order/SuccPred/Limit.lean,Mathlib/Order/WithBot.lean |
3 |
1 |
['github-actions'] |
nobody |
27-52089 27 days ago |
27-62605 27 days ago |
27-63181 27 days |
| 38316 |
tannerduve author:tannerduve |
feat(Order/OmegaCompletePartialOrder): least fixed point and Scott induction |
Adds `ContinuousHom.lfp` for endomorphisms on an ωCPO with `⊥`, as the `ωSup` of the iterate chain from `⊥`, together with `map_lfp`, `isFixedPt_lfp`, `lfp_le_fixed`, `isLeast_lfp`, and the Scott induction theorem `lfp_induction` (specialized from a more general seed-based `ωSup_iterate_induction`).
For `Part.fix`, adds:
* `Part.exists_mem_approx_of_mem_fix`: if `y ∈ Part.fix g x`, some finite approximation of `g` already contains `y`.
* `Part.Fix.approx_eq_iterate_bot` and `Part.Fix.approxChain_eq_iterateChain`: bridges between `Fix.approx`/`approxChain` and `f^[n] ⊥`/`iterateChain`.
* `Part.fix_eq_lfp`: `Part.fix g = ContinuousHom.lfp (.ofFun g hc)` when `g` is ω-Scott continuous.
* `Part.fix_scott_induction`: Scott induction specialized to `Part.fix`.
* `Part.fix_induction_mem`: membership induction on `Part.fix`, derived from `fix_scott_induction`. |
new-contributor |
114/0 |
Mathlib/Control/LawfulFix.lean,Mathlib/Order/OmegaCompletePartialOrder.lean,docs/references.bib |
3 |
2 |
['github-actions'] |
nobody |
27-26914 27 days ago |
39-3016 39 days ago |
39-3311 39 days |
| 38358 |
yuanyi-350 author:yuanyi-350 |
doc(1000.yaml): note more formalised theorems |
---
[](https://gitpod.io/from-referrer/)
|
documentation
maintainer-merge
|
9/2 |
docs/1000.yaml |
1 |
12 |
['YaelDillies', 'github-actions', 'grunweg', 'vihdzp', 'yuanyi-350'] |
nobody |
26-56991 26 days ago |
26-57053 26 days ago |
37-58478 37 days |
| 38871 |
0xTerencePrime author:0xTerencePrime |
feat(Combinatorics/SimpleGraph): add parity lemmas for outer and inner vertices |
Adds three lemmas to `SimpleGraph.DegreeSum`:
- `sum_degrees_option_zmod_two`: the handshaking lemma for `Option I` over ZMod 2
- `degree_none_zmod_two_eq_sum`: simp-normal form of the above
- `card_degree_one_option_eq_outer_zmod_two`: under degree bound ≤ 2, count of degree-1 inner vertices equals outer vertex degree mod 2 |
t-combinatorics
new-contributor
|
65/3 |
Mathlib/Combinatorics/SimpleGraph/DegreeSum.lean |
1 |
6 |
['0xTerencePrime', 'SnirBroshi', 'github-actions'] |
nobody |
25-76399 25 days ago |
26-46627 26 days ago |
26-46396 26 days |
| 38897 |
0xTerencePrime author:0xTerencePrime |
feat(Combinatorics/SetFamily): formalize 1D Sperner's Lemma parity |
Formalizes the 1-dimensional Sperner's Lemma (parity version): given a coloring of
the `n + 1` vertices of a subdivided line segment with two colors (`ZMod 2`), if the
two endpoints have different colors, then the number of color-changing edges is odd.
This is **distinct** from `IsAntichain.sperner` in `SetFamily.LYM`, which concerns
antichains in a power set. This file formalizes the topological/combinatorial parity
statement used as the base case in higher-dimensional Sperner arguments.
## Key declarations
- `SpernerColoring`: type-safe coloring via `Fin (n + 1) → ZMod 2`
- `edgeDiff`: color difference on adjacent vertices, computed in `ZMod 2`
- `totalDiff`: telescoping sum of all edge differences
- `diffEdges`: the `Finset` of bichromatic (color-changing) edges
- `sperner_1d`: main theorem — `Odd (diffEdges c).card`
## Design notes
- Using `Fin (n + 1) → ZMod 2` instead of `ℕ → ZMod 2` makes boundary conditions
unrepresentable at the type level, eliminating out-of-bounds cases entirely.
- The proof reduces to a telescoping sum in `ZMod 2`, using `CharTwo.add_self_eq_zero`
to cancel all interior vertices, avoiding parity case splits.
This is intended as the 1D base case, the approach generalizes to higher-dimensional
Sperner's Lemma in future work.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
133/0 |
Mathlib.lean,Mathlib/Combinatorics/SetFamily/Sperner1D.lean |
2 |
3 |
['github-actions', 'grunweg'] |
nobody |
25-67633 25 days ago |
25-77783 25 days ago |
25-77552 25 days |
| 36815 |
EtienneC30 author:EtienneC30 |
feat: a measurable space structure on the type of continuous maps |
Endow the type `C(X, Y)` of continuous maps from `X` to `Y` with the Borel sigma-algebra coming from the compact-open topology and show that, under some assumptions on `X` and `Y`, this is equal to the restriction of the product sigma-algebra over `X → Y`.
Provide a measurable equivalence between `{f : X → Y // Continuous f}` and `C(X, Y)`.
Co-authored-by: @RemyDegenne
---
[](https://gitpod.io/from-referrer/)
|
t-topology
brownian
t-measure-probability
|
256/0 |
Mathlib.lean,Mathlib/MeasureTheory/Constructions/BorelSpace/ContinuousMap.lean,Mathlib/Topology/Bases.lean,Mathlib/Topology/Basic.lean,Mathlib/Topology/Compactness/Compact.lean,Mathlib/Topology/Separation/Regular.lean |
6 |
27 |
['ADedecker', 'EtienneC30', 'felixpernegger', 'github-actions', 'mathlib-merge-conflicts'] |
nobody |
24-61746 24 days ago |
24-61786 24 days ago |
64-56905 64 days |
| 38951 |
thomaskwaring author:thomaskwaring |
feat(Order/PrimeSeparator): remove unnecessary hypotheses |
In `mem_ideal_sup_principal`, boundedness and distributivity were unused, and in `prime_ideal_of_disjoint_filter_ideal`, boundedness was only used to produce an element of the filter `F`, which is already nonempty by definition.
---
[](https://gitpod.io/from-referrer/)
|
t-order
new-contributor
|
9/19 |
Mathlib/Order/PrimeSeparator.lean |
1 |
2 |
['github-actions'] |
nobody |
24-60324 24 days ago |
24-60411 24 days ago |
24-60180 24 days |
| 38667 |
SnirBroshi author:SnirBroshi |
feat(Order/Hom/Basic): equivalences of `Order{Hom/Embedding/Iso}` |
- `OrderHom`s are equivalent to `RelHom`s of `LE` (unlike `OrderEmbedding`/`OrderIso` they aren't defined using it)
- Congruence equivs for `OrderEmbedding`/`OrderIso` when the two sides are order-isomorphic. This already exists for `OrderHom`.
---
[](https://gitpod.io/from-referrer/)
|
t-order |
55/1 |
Mathlib/Order/Hom/Basic.lean |
1 |
3 |
['SnirBroshi', 'dagurtomas', 'github-actions'] |
nobody |
24-10974 24 days ago |
24-10974 24 days ago |
31-8264 31 days |
| 38979 |
ldct author:ldct |
feat(EReal): simplify nat + ⊤ |
Alternative version of https://github.com/leanprover-community/mathlib4/pull/38975
---
[](https://gitpod.io/from-referrer/)
|
t-data |
28/2 |
Mathlib/Data/EReal/Basic.lean,Mathlib/Data/EReal/Operations.lean,MathlibTest/EReal.lean |
3 |
6 |
['SnirBroshi', 'eric-wieser', 'github-actions', 'ldct', 'leanprover-radar'] |
nobody |
23-41256 23 days ago |
23-41022 23 days ago |
23-40921 23 days |
| 39004 |
zhuyizheng author:zhuyizheng |
chore(ModelTheory): fix hypo of `realize_liftAt` |
changes the hypo of `realize_liftAt` from the incorrect `(hmn : m + n' ≤ n + 1)` to the correct `(hmn : m ≤ n)`
---
[](https://gitpod.io/from-referrer/)
|
t-logic |
2/2 |
Mathlib/ModelTheory/Semantics.lean |
1 |
3 |
['github-actions', 'plp127', 'zhuyizheng'] |
nobody |
23-1485 23 days ago |
23-37614 23 days ago |
23-37383 23 days |
| 38310 |
ZRTMRH author:ZRTMRH |
feat(Combinatorics/Quiver/Schreier): word evaluation and reachability |
Adds word evaluation and reachability results to the Schreier graph API.
* `SchreierGraph.evalWord` : evaluates a word `List (S × Bool)` as an element of the ambient group, where `(s, true)` contributes `ι s` and `(s, false)` contributes `(ι s)⁻¹`.
* `SchreierGraph.evalWord_eq_lift` : agreement with `FreeGroup.lift`.
* `SchreierGraph.evalWord_mem_closure` : every word evaluates into the subgroup generated by `ι`.
* `SchreierGraph.pathFromWord` : a Bool-tagged word yields a path in `Symmetrify (SchreierGraph V ι)` from `x` to `evalWord ι w • x`.
* `SchreierGraph.reachable_iff` : two vertices are connected by a path in the symmetrification iff some element of the subgroup closure carries one to the other.
Follow-up to #36320.
This PR was written with AI assistance (Claude). The code has been reviewed by the author.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-combinatorics
large-import
LLM-generated
|
157/0 |
Mathlib/Combinatorics/Quiver/Schreier.lean |
1 |
2 |
['github-actions'] |
nobody |
22-74339 22 days ago |
39-21413 39 days ago |
39-21182 39 days |
| 39023 |
TBUGTB author:TBUGTB |
feat(Algebra/Order): API lemmas on floor and abs |
Co-authored-by: Etienne Marion @EtienneC30
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
brownian
new-contributor
label:t-algebra$ |
9/0 |
Mathlib/Algebra/Order/Floor/Semiring.lean,Mathlib/Algebra/Order/Ring/Abs.lean |
2 |
3 |
['TBUGTB', 'github-actions'] |
nobody |
22-56065 22 days ago |
22-59254 22 days ago |
22-59023 22 days |
| 39078 |
fpvandoorn author:fpvandoorn |
feat: add lemmas about products over Finset.Iio |
* Mostly useful for `ℕ`
* I added the `Finset.Iic` lemmas by symmetry, but I'm happy to remove them if we think they are redundant.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
29/0 |
Mathlib/Algebra/Order/BigOperators/Group/LocallyFinite.lean |
1 |
1 |
['github-actions'] |
nobody |
21-46710 21 days ago |
21-46790 21 days ago |
21-46559 21 days |
| 37190 |
cjrl author:cjrl |
feat(Combinatorics): Set-Valued Pigeonhole Principle |
This PR contributes two theorems to combinatorics:
- `exists_lt_card_cover_of_card_biUnion_lt_card` is a set-valued version of the pigeonhole principle.
- `sum_card_eq_sum_card_cover_biUnion` is a set theoretic corollary of a double counting result proved for bipartite graphs (`Finset.sum_card_bipartiteAbove_eq_sum_card_bipartiteBelow`). This was needed to prove the above pigeonhole principle.
The motivation for these results is our Latin Square PR #36698. These results were proved in less general terms in that PR, but are independent of Latin Square considerations and so we have generalized and moved them into more relevant files.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-combinatorics
|
38/0 |
Mathlib/Combinatorics/Enumerative/DoubleCounting.lean,Mathlib/Combinatorics/Pigeonhole.lean |
2 |
16 |
['IvanRenison', 'cjrl', 'ghseeli', 'github-actions', 'j-loreaux', 'vlad902'] |
b-mehta assignee:b-mehta |
21-1691 21 days ago |
47-22187 47 days ago |
62-79155 62 days |
| 38309 |
ntapiam author:ntapiam |
feat(Algebra/NonAssoc): dendriform algebras |
Define dendriform semirings and algebras
---
This PR introduces dendriform structures such as dendriform semirings
and algebras, and proves basic facts linking them to their pre-Lie
counterparts.
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
270/0 |
Mathlib.lean,Mathlib/Algebra/NonAssoc/Dendriform/Defs.lean,docs/references.bib |
3 |
5 |
['dagurtomas', 'github-actions', 'ntapiam'] |
ocfnash assignee:ocfnash |
21-1681 21 days ago |
21-53859 21 days ago |
36-58925 36 days |
| 38373 |
Nicola9Falciola author:Nicola9Falciola |
feat (Algebra/FreeAbelianGroup /Finsupp) : The support of non zero element in a freeabeliangroup is non empty |
Add the lemma that for a nonzero a : FreeAbelianGroup X the support of it is non empty.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
3/0 |
Mathlib/Algebra/FreeAbelianGroup/Finsupp.lean |
1 |
7 |
['Nicola9Falciola', 'SnirBroshi', 'github-actions'] |
ocfnash assignee:ocfnash |
21-1673 21 days ago |
36-43816 36 days ago |
37-32026 37 days |
| 38943 |
felixpernegger author:felixpernegger |
feat(Topology/CWComplex/Classical): discrete spaces are CW complexes |
as well as some useful lemmas
This is partly based on code by @scholzhannah
I think this is notable to include, since it is pretty much the only (easy) "topological" sufficient condition for something being a CW complex there is.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
89/3 |
Mathlib/Topology/CWComplex/Classical/Basic.lean,Mathlib/Topology/DiscreteSubset.lean |
2 |
28 |
['felixpernegger', 'github-actions', 'scholzhannah'] |
PatrickMassot assignee:PatrickMassot |
21-1670 21 days ago |
23-58924 23 days ago |
24-72730 24 days |
| 38328 |
astrainfinita author:astrainfinita |
feat: `OrderSupSet` |
This PR introduces `OrderSupSet` and `OrderInfSet`, which are typeclasses expressing that `sSup` (resp., `sInf`) returns the least upper bound (resp., the greatest lower bound) of a set whenever one exists.
This allows us to prove properties about the `sSup` of specific sets (such as `∅`, singletons, finite sets, and `univ`) without any typeclasses asserting the existence of LUBs. For example, `sSup ∅ = ⊥` holds for any type equipped with `OrderBot` `OrderSupSet`, no longer requiring typeclasses like `ConditionallyCompleteLinearOrderBot`.
For a general set `s`, this gives a uniform way to extend results about `IsLUB s a → motive a` to `motive (sSup s)`, `motive (⨆ i, f i)`, `motive (a ⊔ b)`, etc., which allows proof reuse for basic API such as [`csSup_insert`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Order/ConditionallyCompleteLattice/Basic.html#csSup_insert), [`iSup_insert`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Order/CompleteLattice/Basic.html#iSup_insert), and [`sSup_insert`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Order/CompleteLattice/Basic.html#sSup_insert) and downstream code like [`csSup_add`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Algebra/Order/Group/Pointwise/CompleteLattice.html#csSup_add), [`sSup_add`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Algebra/Order/Group/Pointwise/CompleteLattice.html#sSup_add), and [`sup_add`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Algebra/Order/Group/Lattice.html#sup_add).
Furthermore, this allows us to refactor incrementally, reducing the dependency of results about various completeness typeclasses on the specific implementation of `sSup`.
---
[Zulip](https://leanprover.zulipchat.com/#narrow/channel/113488-general/topic/Any.20infimum.20based.20version.20of.20.60OmegaCompletePartialOrder.60.3F)
[](https://gitpod.io/from-referrer/)
|
t-order |
156/73 |
Mathlib/MeasureTheory/OuterMeasure/Induced.lean,Mathlib/Order/Bounds/Basic.lean,Mathlib/Order/Bounds/Defs.lean,Mathlib/Order/CompleteLattice/Basic.lean,Mathlib/Order/CompleteLattice/Defs.lean,Mathlib/Order/SetNotation.lean,Mathlib/Topology/UniformSpace/OfCompactT2.lean |
7 |
16 |
['JovanGerb', 'astrainfinita', 'b-mehta', 'github-actions', 'j-loreaux', 'mathlib-merge-conflicts', 'openendings', 'vihdzp'] |
nobody |
20-66220 20 days ago |
20-66259 20 days ago |
26-10336 26 days |
| 39123 |
SnirBroshi author:SnirBroshi |
chore(Data/Matrix/Basic): mention `mopMatrix` in `transpose{Ring/Alg}Equiv`s docstring and vice versa |
- `RingEquiv.mopMatrix` and `transposeRingEquiv` differ by a `ᵐᵒᵖ` since the latter assumes `CommMagma α` instead of `Mul α`
- `AlgEquiv.mopMatrix` and `transposeAlgEquiv` differ by a `ᵐᵒᵖ` since the latter assumes `CommSemiring α` instead of `Semiring α`
---
Also slightly golfs `RingEquiv.mopMatrix` as a drive-by.
[](https://gitpod.io/from-referrer/)
|
t-data |
18/11 |
Mathlib/Data/Matrix/Basic.lean |
1 |
1 |
['github-actions'] |
nobody |
20-24680 20 days ago |
20-24762 20 days ago |
20-24531 20 days |
| 38587 |
dagurtomas author:dagurtomas |
feat(Tactic/CategoryTheory): concrete category boilerplate |
Adds `mk_concrete_category`, a command for generating the initial boilerplate for concrete categories whose morphisms are given by a bundled function type.
The command creates the wrapper `Hom` type, named category and concrete category instances, `ofHom`, `Hom.hom`, and the basic dsimp lemmas.
It handles parameterized categories such as `ModuleCat`, and has a paired additive/multiplicative form for generating both structures at once (e.g. `MonCat`/`AddMonCat`).
Includes test categories checking the generated declarations.
[](https://gitpod.io/from-referrer/)
|
LLM-generated
t-meta
t-category-theory
|
905/0 |
Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/CategoryTheory/MkConcreteCategory.lean,MathlibTest/CategoryTheory/MkConcreteCategory.lean |
4 |
8 |
['dagurtomas', 'eric-wieser', 'github-actions'] |
adamtopaz assignee:adamtopaz |
20-1351 20 days ago |
22-78490 22 days ago |
22-79020 22 days |
| 38855 |
SnirBroshi author:SnirBroshi |
feat(Order/ConditionallyCompleteLattice/Indexed): `≤` version of `ciSup_or'` for `ConditionallyCompleteLattice` |
Deprime `ciSup_or'` because there's no `ciSup_or`, and add a `≤` version (and dual) for `ConditionallyCompleteLattice`.
Only `≤` because equality does not hold when `p ≠ q` without `sSup ∅ = ⊥`.
---
`ciSup_or'` can't have a dual because there's no dual to `ConditionallyCompleteLinearOrderBot`.
[](https://gitpod.io/from-referrer/)
|
t-order |
8/1 |
Mathlib/Order/ConditionallyCompleteLattice/Indexed.lean |
1 |
1 |
['github-actions'] |
nobody |
19-63261 19 days ago |
26-84469 26 days ago |
26-84238 26 days |
| 38489 |
Jun2M author:Jun2M |
feat(Topology/Algebra/InfiniteSum): Generalize ENNReal lemmas |
This PR generalizes many theorems in Topology/Algebra/InfiniteSum/ENNReal.lean from `ENNREal` to any type that satisfies a list of order-related instances, mostly
`[CommMonoid α] [CompleteLattice α] [CanonicallyOrderedMul α] [TopologicalSpace α] [SupConvergenceClass α]`
Deprecation of the original `ENNReal` lemmas are done in the next PR: #38193.
Related Zulip thread: [#Is there code for X? > Summing `ENat`s without topology](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Summing.20.60ENat.60s.20without.20topology/with/588756615)
---
[](https://gitpod.io/from-referrer/)
|
|
261/3 |
Mathlib/MeasureTheory/Measure/MeasureSpace.lean,Mathlib/MeasureTheory/OuterMeasure/OfFunction.lean,Mathlib/Topology/Algebra/InfiniteSum/Basic.lean,Mathlib/Topology/Algebra/InfiniteSum/Order.lean |
4 |
7 |
['Jun2M', 'SnirBroshi', 'github-actions', 'wwylele'] |
nobody |
19-13895 19 days ago |
19-13972 19 days ago |
35-3786 35 days |
| 38649 |
chrisflav author:chrisflav |
chore(RingTheory): equality of linear map with values in finite module spreads out |
We add some corollaries of `Module.Finite.exists_smul_of_comp_eq_of_isLocalizedModule`.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
large-import
|
75/1 |
Mathlib/Algebra/Module/FinitePresentation.lean,Mathlib/RingTheory/Localization/BaseChange.lean,Mathlib/RingTheory/Localization/Module.lean |
3 |
2 |
['github-actions'] |
alreadydone assignee:alreadydone |
19-1270 19 days ago |
31-40419 31 days ago |
31-40188 31 days |
| 39107 |
SnirBroshi author:SnirBroshi |
feat(Geometry/Manifold/ChartedSpace): `H ≃ₜ M` → `ChartedSpace H M` |
---
I thought it was strange that `Homeomorph`s didn't have this easy dot-notation, though I'm not familiar with this part of the library so I might be missing something.
[](https://gitpod.io/from-referrer/)
|
t-differential-geometry |
6/0 |
Mathlib/Geometry/Manifold/ChartedSpace.lean |
1 |
1 |
['github-actions'] |
PatrickMassot assignee:PatrickMassot |
19-1259 19 days ago |
20-66187 20 days ago |
20-65956 20 days |
| 39157 |
vihdzp author:vihdzp |
feat: `Nat.cast` commutes with addition |
---
[](https://gitpod.io/from-referrer/)
|
|
26/9 |
Mathlib/Data/Nat/Cast/Commute.lean,Mathlib/SetTheory/Ordinal/Arithmetic.lean |
2 |
2 |
['github-actions', 'plp127'] |
nobody |
18-41577 18 days ago |
19-16642 19 days ago |
19-16411 19 days |
| 39219 |
WenrongZou author:WenrongZou |
feat(FieldTheory/Finite): add variant theorems for `expand_card` |
Add `MvPolynomial, MvPowerSeries, PowerSeries` version of `FiniteField.expand_card`, which is only for polynomial.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
large-import
label:t-algebra$ |
45/4 |
Mathlib/FieldTheory/Finite/Basic.lean,Mathlib/LinearAlgebra/Matrix/Charpoly/FiniteField.lean,Mathlib/RingTheory/MvPolynomial/Expand.lean,Mathlib/RingTheory/MvPowerSeries/Expand.lean,Mathlib/RingTheory/PowerSeries/Expand.lean |
5 |
1 |
['github-actions'] |
nobody |
18-16964 18 days ago |
18-17005 18 days ago |
18-17006 18 days |
| 37399 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Paths): `IsPath` and `Nil` lemmas |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
10/3 |
Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Paths.lean |
2 |
8 |
['Rida-Hamadani', 'SnirBroshi', 'YaelDillies', 'github-actions'] |
YaelDillies assignee:YaelDillies |
18-15160 18 days ago |
59-81209 59 days ago |
59-81122 59 days |
| 36863 |
artie2000 author:artie2000 |
refactor(Algebra/Order/Ring/Ordering): unbundle `RingPreordering` |
The current design for [RingPreordering](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Algebra/Order/Ring/Ordering/Defs.html#RingPreordering) ran into issues at PR #32077. This PR unbundles [RingPreordering](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Algebra/Order/Ring/Ordering/Defs.html#RingPreordering) into a class predicate on [Subsemiring](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Algebra/Ring/Subsemiring/Defs.html#Subsemiring), generalising the material on supports as far as possible.
Zulip thread: https://leanprover.zulipchat.com/#narrow/channel/116395-maths/topic/Ring.20orderings.20-.20structure.20or.20predicate.3F/with/562594050
See #37298 for the analogous change to group and ring cones.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
large-import
label:t-algebra$ |
455/87 |
Mathlib.lean,Mathlib/Algebra/Order/Ring/Ordering/Basic.lean,Mathlib/Algebra/Order/Ring/Ordering/Defs.lean,Mathlib/Algebra/Ring/Subsemiring/Support.lean |
4 |
14 |
['artie2000', 'chrisflav', 'github-actions', 'mathlib-merge-conflicts'] |
eric-wieser assignee:eric-wieser |
18-13908 18 days ago |
18-13908 18 days ago |
60-54909 60 days |
| 39162 |
anovickis author:anovickis |
feat(Topology/PartitionOfUnity): add pointwise_decomposition_finsum + companions |
Add three short lemmas to `Mathlib/Topology/PartitionOfUnity.lean` extending the existing `PartitionOfUnity` API:
- `pointwise_decomposition_finsum` — for `f : X → ℝ` and `x ∈ s`, `f x = ∑ᶠ i, ρ i x · f x`. This is the pointwise step that lifts to integral linearity in measure-theoretic PoU integration: `∫_s f dμ = ∑ᶠ i, ∫_s (ρ i · f) dμ`.
- `one_minus_sum_nonneg` — `0 ≤ 1 - ∑ᶠ i, ρ i x`. Direct rearrangement of the existing `sum_le_one` field; useful as a complement-mass remainder bound in chart-by-chart estimates.
- `abs_le_one` — `|ρ i x| ≤ 1`. Combines the existing `nonneg` and `le_one`; convenience for absolute-value bounds.
All three are short proofs using existing structure fields (`sum_eq_one`, `sum_le_one`, `nonneg`, `le_one`).
These came up while writing chart-by-chart Stokes-on-manifold estimates where one wants to decompose `∫_M f` into chart-supported pieces using a partition of unity. The pointwise identity is the obvious first step; the other two are complementary algebraic bounds that show up in remainder estimates.
---
🤖 Generated with [Claude Code](https://claude.com/claude-code) |
t-topology
new-contributor
LLM-generated
|
27/0 |
Mathlib/Topology/PartitionOfUnity.lean |
1 |
2 |
['github-actions'] |
urkud assignee:urkud |
18-1646 18 days ago |
18-83967 18 days ago |
18-83736 18 days |
| 39239 |
alainchmt author:alainchmt |
feat(FieldTheory/Finite): irreducible polynomial divides X^q^n - X iff degree divides n |
---
Add the theorem saying that, for an irreducible polynomial `f` over a finite field `K`, the degree of `f` divides `n` if and only if `f` divides `X ^ (Nat.card K) ^ n - X`. Include auxiliary lemmas.
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
34/0 |
Mathlib/FieldTheory/Finite/Extension.lean,Mathlib/FieldTheory/Minpoly/Field.lean |
2 |
2 |
['github-actions'] |
nobody |
17-57219 17 days ago |
17-57308 17 days ago |
17-57077 17 days |
| 39195 |
linesthatinterlace author:linesthatinterlace |
feat(Logic/Function/Defs): Add dcomp lemmas |
This PR adds API lemmas about `dcomp` that were previously missing.
---
[](https://gitpod.io/from-referrer/)
|
t-logic |
13/0 |
Mathlib/Logic/Function/Defs.lean |
1 |
6 |
['github-actions', 'linesthatinterlace', 'plp127'] |
nobody |
17-46478 17 days ago |
18-47977 18 days ago |
18-47746 18 days |
| 39230 |
bryangingechen author:bryangingechen |
chore: extract API from #38807 and golf |
I wanted to understand why these two proofs in #38807 were long (and also play around more with the API in this corner of the library) so I walked through them with Claude Opus.
prepared with Claude code
|
t-order
LLM-generated
|
23/37 |
Mathlib/Order/Bounds/Basic.lean,Mathlib/Order/DirSupClosed.lean |
2 |
2 |
['github-actions', 'vihdzp'] |
nobody |
17-10841 17 days ago |
17-85477 17 days ago |
17-85246 17 days |
| 36202 |
vihdzp author:vihdzp |
feat: more theorems on the Cantor normal form |
We also remove some redundant assumptions.
Used in the CGT repo.
---
[](https://gitpod.io/from-referrer/)
|
t-set-theory |
68/17 |
Mathlib/SetTheory/Ordinal/CantorNormalForm.lean |
1 |
21 |
['SnirBroshi', 'YaelDillies', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp'] |
YaelDillies assignee:YaelDillies |
16-59163 16 days ago |
65-58712 65 days ago |
84-50442 84 days |
| 36388 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/AdjMatrix): submatrices and homomorphisms |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
maintainer-merge
|
73/3 |
Mathlib/Combinatorics/SimpleGraph/AdjMatrix.lean |
1 |
19 |
['SnirBroshi', 'YaelDillies', 'eric-wieser', 'github-actions', 'mathlib-merge-conflicts', 'themathqueen'] |
nobody |
16-51044 16 days ago |
17-1222 17 days ago |
46-37946 46 days |
| 39279 |
jayscambler author:jayscambler |
feat(Cryptography/Sigma): Schnorr sigma protocol and signature scheme |
Adds `Mathlib/Cryptography/Sigma/Schnorr.lean`. New file in a new top-level directory; mathlib currently has no `Mathlib/Cryptography/`, so I've taken `Mathlib/Cryptography/Sigma/` as the natural home for sigma-protocol formalizations.
The file proves the three defining properties of Schnorr's identification scheme as a sigma protocol:
- `Schnorr.correct`: completeness. Honest verifier accepts honest signer's transcript.
- `Schnorr.specialSoundness`: from two accepting transcripts sharing the commitment but using different challenges `c, c'`, the witness `x = (s - s') / (c - c')` is recovered. Needs `q` prime so `c - c'` is invertible in `ZMod q`.
- `Schnorr.hvzkAccepts`: the HVZK simulator `g^s · (y^c)⁻¹` always yields accepting transcripts. This is the structural-correctness half of HVZK only; the distributional indistinguishability statement is a separate result and not in this PR.
On top of the sigma protocol there's `Schnorr.Signature.{keyGen, sign, verify, correct}` wrapping it as a Fiat-Shamir signature scheme; `Schnorr.Signature.correct` is a one-line corollary of `Schnorr.correct`.
Two auxiliary lemmas, `Schnorr.gpow_sub` and `Schnorr.gpow_mul`, bridge `ZMod q` arithmetic and group exponentiation under `Fintype.card G = q`. They're local to this file for now because the surrounding `gpow` API is itself cryptography-specific; if a general `ZMod q`-graded group action framework lands in mathlib later, both lemmas would become instances of it.
There's also a small `example` instantiating everything on `Multiplicative (ZMod q)` for `Fact q.Prime` to show the API typechecks. That instantiation is a toy (DLOG is trivial in that group), but it confirms the abstraction is usable.
**AI disclosure**: this PR was a collaboration between myself, Grey Haven's autocontext and Claude Opus 4.7 (Anthropic). I read each line and built locally on current master. (strawberry has three r's) |
new-contributor
LLM-generated
|
352/0 |
Mathlib.lean,Mathlib/Cryptography/Sigma/Schnorr.lean |
2 |
2 |
['github-actions'] |
nobody |
16-34661 16 days ago |
16-34740 16 days ago |
16-34999 16 days |
| 35255 |
vlad902 author:vlad902 |
feat(SimpleGraph): `cycleGraph.IsContained` in every graph with a cycle |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
35/0 |
Mathlib/Combinatorics/SimpleGraph/Circulant.lean |
1 |
3 |
['github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
nobody |
16-31301 16 days ago |
31-17773 31 days ago |
31-18489 31 days |
| 38114 |
javgomzar author:javgomzar |
feat(FinitelyPresentedGroup): add finite groups instance |
Add IsFinitelyPresented instance for finite groups.
Co-authored-by: Hang Lu Su , Thomas Browning
---
[](https://gitpod.io/from-referrer/)
|
t-group-theory
new-contributor
large-import
|
31/2 |
Mathlib/GroupTheory/FinitelyPresentedGroup.lean,Mathlib/GroupTheory/FreeGroup/Basic.lean |
2 |
33 |
['github-actions', 'javgomzar', 'kbuzzard', 'mathlib-merge-conflicts', 'plp127', 'tb65536', 'vihdzp'] |
mattrobball assignee:mattrobball |
16-26271 16 days ago |
16-26307 16 days ago |
39-23813 39 days |
| 34855 |
staroperator author:staroperator |
feat(Order): use `to_dual` for `PFilter` |
This PR redefines `PFilter` to get rid of `OrderDual` and uses `to_dual` to translate theorems. The whole file of `PFilter` is now deprecated.
Some changes:
- To align with `Filter`, the order on `PFilter` is changed to the reversed set inclusion. Ultrafilters, the dual notion of maximal ideals, become minimal in this order.
- `to_dual` does not work on `sequenceOfCofinals`. I left `Order.Cofinal` and the Rasiowa–Sikorski lemma not `to_dual`-ized, and we should move them to a separate file later.
- `IsLEChain` is added to tag `to_dual`.
- `IsCoatom.isProper`/`IsCoatom.isMaximal` is deprecated by `Order.Ideal.isProper_of_isCoatom`/`Order.Ideal.isMaximal_of_isProper`, since this result is special to ideals while `IsCoatom` namespace should be for orders in general.
---
- [x] depends on: #34820
---
[](https://gitpod.io/from-referrer/)
|
t-order |
292/242 |
Mathlib/Order/Atoms.lean,Mathlib/Order/BooleanAlgebra/Basic.lean,Mathlib/Order/BooleanAlgebra/Defs.lean,Mathlib/Order/CompleteLattice/Defs.lean,Mathlib/Order/Ideal.lean,Mathlib/Order/PFilter.lean,Mathlib/Order/Preorder/Chain.lean,Mathlib/Order/PrimeIdeal.lean,Mathlib/Order/PrimeSeparator.lean,Mathlib/Order/ZornAtoms.lean,Mathlib/RingTheory/IdealFilter/Basic.lean,Mathlib/RingTheory/IdealFilter/Topology.lean,Mathlib/Tactic/Translate/ToDual.lean |
13 |
4 |
['github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
nobody |
16-19082 16 days ago |
16-18860 16 days ago |
28-41941 28 days |
| 37928 |
AlexeyMilovanov author:AlexeyMilovanov |
refactor(Computability.Encoding): unbundle Γ and remove FinEncoding |
This PR unbundles the alphabet `Γ` from the `Encoding` structure and completely removes `FinEncoding`.
`Encoding`: The alphabet `Γ` is now an explicit parameter: `structure Encoding (α : Type u) (Γ : Type v)`.
`FinEncoding`: Removed. Finiteness is now handled via standard typeclasses (e.g., `[Fintype Γ] (e : Encoding α Γ)`).
Combinators: Functions like `finEncodingPair` are simplified to `encodingPair`, dropping the `fin` prefix and `[Fintype]` requirements where no longer needed.
Downstream: Mechanically updated `Mathlib.Computability` and `Mathlib.ModelTheory` to pass the explicit `Γ` and use `[Fintype Γ]` where `FinEncoding` was previously required.
|
new-contributor
maintainer-merge
|
87/67 |
Mathlib/Computability/Encoding.lean,Mathlib/ModelTheory/Encoding.lean |
2 |
9 |
['AlexeyMilovanov', 'dagurtomas', 'github-actions', 'vihdzp'] |
nobody |
16-6132 16 days ago |
22-57110 22 days ago |
48-36735 48 days |
| 38816 |
tb65536 author:tb65536 |
refactor(GroupTheory/Finiteness): make duplicate definitions into abbrevs |
The definitions `Submonoid.FG`, `Group.FG`, and `Subgroup.FG` are all equivalent to `Monoid.FG`, so I've made them into abbrevs. In the future we might even want to consider deprecating all but one to avoid having four ways to write the same thing.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-group-theory
label:t-algebra$ |
140/122 |
Mathlib/Algebra/AffineMonoid/Irreducible.lean,Mathlib/GroupTheory/Finiteness.lean,Mathlib/GroupTheory/MonoidLocalization/Finite.lean,Mathlib/GroupTheory/Schreier.lean,Mathlib/ModelTheory/Arithmetic/Presburger/Semilinear/Basic.lean,Mathlib/ModelTheory/Arithmetic/Presburger/Semilinear/Defs.lean,Mathlib/RingTheory/FiniteType.lean,Mathlib/RingTheory/Finiteness/Defs.lean,Mathlib/RingTheory/Localization/InvSubmonoid.lean |
9 |
5 |
['eric-wieser', 'github-actions', 'j-loreaux', 'tb65536'] |
mattrobball assignee:mattrobball |
16-1273 16 days ago |
28-24196 28 days ago |
28-23966 28 days |
| 39341 |
drocta author:drocta |
feat(Algebra/Colimit/DirectLimit): add DirectLimit.(NonUnital)StarAlgebra.(lift/of) maps and associated lemmas |
add the `of` and `lift` maps for `DirectLimit.StarAlgebra` and `DirectLimit.NonUnitalStarAlgebra`, as well as the associated lemmas, `of_f`, `lift_comp_of`, `lift_of`, and `hom_ext` for each. Also make `DirectLimit.NonUnitalAlgebra` only require `[Monoid R]` rather than `[CommSemiring R]`.
---
Use of AI: I again asked ChatGPT for some advice about some things about this code. I can personally vouch for all of the code I'm submitting, and that I understand all of it.
This is the third part of my project towards supporting direct limits of $C^∗$ -algebras (as I described [on Zulip](https://leanprover.zulipchat.com/#narrow/channel/113489-new-members/topic/Early.20feedback.20on.20approach.20towards.20formalizing.20UHF.20algebras.3F) ).
This PR adds an import of `Mathlib.Algebra.Star.StarAlgHom` (because it needs `StarAlgHom` and `NonUnitalStarAlgHom`) replacing/encompassing the previously added imports of `Mathlib.Algebra.Star.StarRingHom` and `Mathlib.Algebra.Algebra.NonUnitalHom` (added in PR #38308 and #38672 respectively). |
t-algebra
new-contributor
label:t-algebra$ |
100/3 |
Mathlib/Algebra/Colimit/DirectLimit.lean |
1 |
2 |
['github-actions'] |
nobody |
16-684 16 days ago |
16-3376 16 days ago |
16-3145 16 days |
| 38199 |
vihdzp author:vihdzp |
chore: add items to set theory overview |
---
[](https://gitpod.io/from-referrer/)
|
documentation
t-set-theory
maintainer-merge
|
11/2 |
docs/overview.yaml |
1 |
5 |
['SnirBroshi', 'github-actions', 'joneugster', 'vihdzp'] |
alreadydone assignee:alreadydone |
15-43123 15 days ago |
41-61899 41 days ago |
41-61767 41 days |
| 39373 |
yuanyi-350 author:yuanyi-350 |
refactor(NumberTheory): golf `Mathlib/NumberTheory/ModularForms/CongruenceSubgroups` |
- simplifies `Gamma_mem` to a single `simp` proof via `Gamma_mem'` and `SpecialLinearGroup.ext_iff`
- shortens `ModularGroup_T_pow_mem_Gamma` and the `Gamma0` closure proofs with direct `simp`/`simpa` arguments
Extracted from #38144
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
|
4/22 |
Mathlib/NumberTheory/ModularForms/CongruenceSubgroups.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
15-33758 15 days ago |
15-35491 15 days ago |
15-35260 15 days |
| 39374 |
yuanyi-350 author:yuanyi-350 |
refactor(NumberTheory): golf `Mathlib/NumberTheory/ModularForms/Derivative` |
- rewrites `normalizedDerivOfComplex_sub` to reuse the additive and negation lemmas instead of reproving the subtraction formula pointwise
Extracted from #38144
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
|
4/10 |
Mathlib/NumberTheory/ModularForms/Derivative.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
15-33552 15 days ago |
15-35488 15 days ago |
15-35257 15 days |
| 39375 |
yuanyi-350 author:yuanyi-350 |
refactor(NumberTheory): golf `Mathlib/NumberTheory/ModularForms/SlashActions` |
- streamlines `prod_slash_sum_weights` by letting `simp` handle the empty case and removing the redundant singleton split in the inductive step
Extracted from #38144
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
|
1/5 |
Mathlib/NumberTheory/ModularForms/SlashActions.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
15-33395 15 days ago |
15-35485 15 days ago |
15-35254 15 days |
| 39376 |
yuanyi-350 author:yuanyi-350 |
refactor(NumberTheory): golf `Mathlib/NumberTheory/RamificationInertia/Basic` |
- shortens `quotientToQuotientRangePowQuotSucc_surjective` by switching the ideal-factor argument to `irreducible_pow_sup` and `count_normalizedFactors_eq` after isolating the span hypotheses
Extracted from #38144
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
|
4/10 |
Mathlib/NumberTheory/RamificationInertia/Basic.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
15-33223 15 days ago |
15-35483 15 days ago |
15-35252 15 days |
| 36541 |
BGuillemet author:BGuillemet |
feat(CategoryTheory): define internal equivalence relations |
Define internal equivalence relations in any category `C`, as a structure on parallel pairs of morphisms.
Prove that equivalence relations on types are equivalence relations in the category of types.
Prove that kernel pairs are equivalence relations.
Define (universally) effective equivalence relations, and a associated class for categories in which every equivalence relation is effective universal.
Prove that an effective equivalence relation yields a coequalizer diagram, and that the associated projection on the "quotient" of the relation is a regular epimorphism.
---
[](https://gitpod.io/from-referrer/)
|
t-category-theory |
320/0 |
Mathlib.lean,Mathlib/CategoryTheory/EquivalenceRelation.lean,Mathlib/CategoryTheory/Limits/Shapes/RegularMono.lean |
3 |
26 |
['BGuillemet', 'chrisflav', 'dagurtomas', 'github-actions', 'robin-carlier'] |
b-mehta assignee:b-mehta |
15-15319 15 days ago |
15-46485 15 days ago |
36-58918 36 days |
| 39392 |
jayscambler author:jayscambler |
feat(Cryptography): one-time pad and Shannon perfect secrecy |
Adds `Mathlib/Cryptography/OTP.lean`. One-time pad over an arbitrary
finite abelian group `G`:
- `OTP.encrypt k m := m + k`, `OTP.decrypt k c := c - k`.
- `OTP.correct`: `decrypt k (encrypt k m) = m`, by `abel`.
- `OTP.perfect_secrecy`: for any `m₀, m₁`, the distributions of
`encrypt k m₀` and `encrypt k m₁` over uniform `k` are equal;
both reduce to `PMF.uniformOfFintype G`. Proof goes via
`Equiv.addLeft`.
Independent of the Schnorr PR (#39279); no shared definitions. Unlike
everything else likely to live under `Mathlib/Cryptography/`, the
security guarantee here is information-theoretic, not computational.
**AI disclosure**: this PR was a collaboration between myself, Grey
Haven's autocontext and Claude Opus 4.7 (Anthropic). I read each
line and built locally on current master. (strawberry has three r's) |
new-contributor
LLM-generated
|
76/0 |
Mathlib.lean,Mathlib/Cryptography/OTP.lean |
2 |
3 |
['MrBrain295', 'github-actions'] |
nobody |
14-83613 14 days ago |
15-19687 15 days ago |
15-19456 15 days |
| 37745 |
AntoineChambert-Loir author:AntoineChambert-Loir |
feat(RingTheory/AugmentationIdeal): base change for augmentation ideals |
Base change for augmentation ideals
Co-authored with: @mariainesdff
---
- [x] depends on: #37744
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
t-algebra
large-import
label:t-algebra$ |
441/1 |
Mathlib.lean,Mathlib/Algebra/Algebra/Hom.lean,Mathlib/Algebra/Algebra/Subalgebra/Basic.lean,Mathlib/Algebra/Module/Submodule/Range.lean,Mathlib/LinearAlgebra/Projection.lean,Mathlib/LinearAlgebra/Span/Defs.lean,Mathlib/LinearAlgebra/TensorProduct/Projection.lean,Mathlib/LinearAlgebra/TensorProduct/RightExactness.lean,Mathlib/LinearAlgebra/TensorProduct/Submodule.lean,Mathlib/Order/Disjoint.lean,Mathlib/RingTheory/Ideal/IsAugmentation.lean,Mathlib/RingTheory/TensorProduct/Basic.lean |
12 |
18 |
['AntoineChambert-Loir', 'dagurtomas', 'github-actions', 'mathlib-dependent-issues'] |
nobody |
14-52952 14 days ago |
14-53023 14 days ago |
15-26768 15 days |
| 36218 |
Brian-Nugent author:Brian-Nugent |
feat(CategoryTheory): Add exact sequences for Sheaf Cohomology |
In this PR, I add the long exact sequence for sheaf cohomology as well as prove that it is functorial. Since sheaf cohomology is defined in terms of `Ext`, this is done using the covariant sequence for `Ext`.
---
- [x] depends on: #34742
[](https://gitpod.io/from-referrer/)
|
t-category-theory |
229/1 |
Mathlib.lean,Mathlib/Algebra/Homology/SpectralObject/Page.lean,Mathlib/CategoryTheory/ComposableArrows/Basic.lean,Mathlib/CategoryTheory/Sites/SheafCohomology/ExactSequences.lean |
4 |
29 |
['Brian-Nugent', 'dagurtomas', 'github-actions', 'joelriou', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
robin-carlier assignee:robin-carlier |
14-29821 14 days ago |
14-29821 14 days ago |
16-55243 16 days |
| 38731 |
martinwintermath author:martinwintermath |
feat(LinearAlgebra/AffineSpace/AffineSubspace): using `AffineSubspace.direction` to reinterpret `AffineSubspace` as `Submodule` |
* add `AffineSubspace.vsub_self_of_zero_mem` that states `s -ᵥ s = s ` if `0 ∈ s`
* add `AffineSubspace.direction_eq_self_of_zero_mem` that states that if `0 ∈ s`, then the directions coerce back to the affine subspace.
* add corresponding `CanLift` instance.
* modify doc-string of `AffineSubspace.direction` to state that this can be used for reinterpretation of an affine subspace as a submodule.
* add `Coe` instance based on `Submodule.toAffineSubspace` and adds corresponding @[coe] attribute.
The PR also performs a slight cleanup of the file: statements about `SetLike` or `Submodule.toAffineSubspace` have been moved closer to their respective definitions.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
56/26 |
Mathlib/LinearAlgebra/AffineSpace/AffineSubspace/Defs.lean |
1 |
3 |
['github-actions', 'wwylele'] |
themathqueen assignee:themathqueen |
14-1710 14 days ago |
30-26461 30 days ago |
30-27381 30 days |
| 39438 |
SnirBroshi author:SnirBroshi |
chore(Order/WellFounded): use `to_dual` |
Creates `argmax`/`argmaxOn` duals to the existing `argmin`/`argminOn`,
and `WellFoundedLT.min`/`WellFoundedGT.max` in order to properly dualize `WellFounded.min_le`.
Some theorems about `WellFounded{LT/GT}` which didn't have a dual before have to be renamed to make room,
e.g. `StrictMono.range_inj` is renamed to `StrictMono.range_inj_of_wellFoundedLT`.
---
This is blocking dualizing things in `ConditionallyCompleteLattice/Basic.lean`.
`WellFounded.min_le` has ~30 usages in ~10 files, so deprecating it should probably happen in a separate PR.
[](https://gitpod.io/from-referrer/)
|
t-order |
80/34 |
Mathlib/Data/Finset/Sort.lean,Mathlib/Order/Hom/Set.lean,Mathlib/Order/WellFounded.lean,Mathlib/SetTheory/Ordinal/Enum.lean |
4 |
5 |
['SnirBroshi', 'github-actions', 'vihdzp'] |
nobody |
13-86019 13 days ago |
13-86091 13 days ago |
14-8056 14 days |
| 39106 |
SnirBroshi author:SnirBroshi |
feat(LinearAlgebra/Matrix/Reindex): `AddEquiv` and `RingEquiv` |
We had `Matrix.reindex` bundled as a `LinearEquiv` and an `AlgEquiv`,
and this bundles it as an `AddEquiv` and a `RingEquiv`.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
158/43 |
Mathlib/LinearAlgebra/Matrix/Basis.lean,Mathlib/LinearAlgebra/Matrix/Charpoly/Coeff.lean,Mathlib/LinearAlgebra/Matrix/Reindex.lean,Mathlib/LinearAlgebra/Matrix/Transvection.lean |
4 |
10 |
['SnirBroshi', 'eric-wieser', 'github-actions', 'themathqueen'] |
nobody |
13-85578 13 days ago |
17-1865 17 days ago |
17-23836 17 days |
| 37707 |
MavenRain author:MavenRain |
feat(Combinatorics/SimpleGraph): add IsMaximalClique/IsMaximalIndepSet, refactor IsMaximum* to MaximalFor |
Addresses #34962
|
new-contributor
t-combinatorics
|
63/31 |
Mathlib/Combinatorics/SimpleGraph/Clique.lean |
1 |
6 |
['MavenRain', 'SnirBroshi', 'eric-wieser', 'github-actions'] |
nobody |
13-67336 13 days ago |
13-67408 13 days ago |
13-68817 13 days |
| 38317 |
WenrongZou author:WenrongZou |
feat(Date/Choose): add some lemmas about choose of prime pow |
In this PR, I add some lemma about choose of prime pow.
1) For primes `p` and positive integer `n`, assume that for all `i ∈ Icc 1 (n - 1)`, `choose n i` congruent to `0` module `p`, then `n = p ^ multiplicity p n`.
2) For a prime power `n`, the greatest common divisor of `choose n 1, ⋯, choose n (n - 1)` is actually the minimal prime factor of `n`.
3) For a natural number `n` greater than `1`, assume that `n` is not a prime power, then the greatest common divisor of `choose n 1, ⋯, choose n (n - 1)` is `1`.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
98/0 |
Mathlib/Data/Nat/Choose/Lucas.lean |
1 |
5 |
['WenrongZou', 'github-actions', 'joneugster'] |
joneugster assignee:joneugster |
13-60801 13 days ago |
13-60601 13 days ago |
39-11058 39 days |
| 39368 |
gasparattila author:gasparattila |
feat: homogenization of an affine space |
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
401/0 |
Mathlib.lean,Mathlib/LinearAlgebra/AffineSpace/Homogenization.lean,docs/references.bib |
3 |
15 |
['eric-wieser', 'gasparattila', 'github-actions'] |
nobody |
13-44218 13 days ago |
15-35724 15 days ago |
15-36695 15 days |
| 39472 |
NoahW314 author:NoahW314 |
feat(RingTheory/MvPolynomial/Homogeneous): add homogeneous lemmas |
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
large-import
|
74/2 |
Mathlib/Data/Finsupp/Weight.lean,Mathlib/RingTheory/MvPolynomial/Homogeneous.lean,Mathlib/RingTheory/MvPolynomial/WeightedHomogeneous.lean |
3 |
1 |
['github-actions'] |
nobody |
13-23267 13 days ago |
13-23337 13 days ago |
13-23300 13 days |
| 37720 |
cjrl author:cjrl |
feat(Data/Fintype/Card): existsUnique_notMem_image_of_injective_of_card_succ |
This pull requests adds a small theorem `existsUnique_notMem_image_of_injective_of_card_succ` to `Mathlib/Data/Fintype/Card` that says given an injective map f : α → β such that β has cardinality one more than α, there exists a unique element of β not in the image of f.
This can be viewed as going in the opposite direction of `card_lt_of_injective_of_notMem`.
This little fact is needed for our Latin Square PR #36698.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
t-set-theory
|
19/0 |
Mathlib/Data/Finset/Card.lean,Mathlib/Data/Fintype/Card.lean |
2 |
10 |
['IvanRenison', 'cjrl', 'dagurtomas', 'ghseeli', 'github-actions'] |
nobody |
12-84316 12 days ago |
12-84316 12 days ago |
50-54941 50 days |
| 35197 |
j-loreaux author:j-loreaux |
feat: Hölder framework for `lp` spaces |
---
- [ ] depends on: #35152
- [ ] depends on: #35198
[](https://gitpod.io/from-referrer/)
|
t-analysis |
311/9 |
Mathlib.lean,Mathlib/Analysis/Normed/Lp/LpEquiv.lean,Mathlib/Analysis/Normed/Lp/lpHolder.lean,Mathlib/Analysis/Normed/Lp/lpSpace.lean,Mathlib/Analysis/Normed/Operator/Basic.lean,Mathlib/Tactic/Linter/TextBased.lean |
6 |
13 |
['github-actions', 'j-loreaux', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mcdoll', 'mike1729', 'themathqueen'] |
themathqueen assignee:themathqueen |
12-82604 12 days ago |
36-31579 36 days ago |
55-34127 55 days |
| 39443 |
justus-springer author:justus-springer |
feat(Data/Set/Image): `nonempty_preimage_iff` |
Basically a converse to `nonempty_of_nonempty_preimage`.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
4/0 |
Mathlib/Data/Set/Image.lean |
1 |
4 |
['Paul-Lez', 'github-actions', 'justus-springer', 'urkud'] |
nobody |
12-66417 12 days ago |
14-11194 14 days ago |
14-10963 14 days |
| 33392 |
AntoineChambert-Loir author:AntoineChambert-Loir |
feat(LinearAlgebra/Transvection/Generation): non-exceptional case in Dieudonné's theorem |
We prove the theorem of [Dieudonné-1955][J. Dieudonné, “Sur les générateurs
des groupes classiques”].
Let `K` be a division ring and `V` be a `K`-module.
* `LinearEquiv.mem_transvections_pow_mul_dilatransvections_of_fixedReduce_eq_one`:
If `e.fixedReduce = 1`, then `e` can be written as the product
of `finrank K (V ⧸ e.fixedSubmodule) - 1` transvections
and one dilatransvection.
This is the first part of the non-exceptional case in Dieudonné's theorem.
(This statement is not interesting when `e = 1`.)
* `LinearEquiv.mem_transvections_pow_mul_dilatransvections_of_fixedReduce_ne_smul_id`:
If `e.fixedReduce` is not a homothety, then `e` can be written as the product
of `finrank K (V ⧸ e.fixedSubmodule) - 1` transvections and one dilatransvection.
This is the second part of the non-exceptional case in Dieudonné's theorem.
* `LinearEquiv.IsExceptional`:
A linear equivalence `e : V ≃ₗ[K] V` is exceptional if `1 < finrank K (V ⧸ e.fixedSubmodule)`
and if `e.fixedReduce` is a nontrivial homothety.
* `LinearEquiv.mem_dilatransvections_pow_of_notIsExceptional`:
This is the non-exceptional case in Dieudonné's theorem,
as a combination of the two preceding statements.
---
- [x] depends on: #33348
- [x] depends on: #33282
- [x] depends on: #33347
- [ ] depends on: #33387
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
551/0 |
Mathlib.lean,Mathlib/LinearAlgebra/Center.lean,Mathlib/LinearAlgebra/LinearIndependent/Lemmas.lean,Mathlib/LinearAlgebra/Transvection/Generation.lean |
4 |
16 |
['AntoineChambert-Loir', 'dagurtomas', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot'] |
joelriou assignee:joelriou |
12-62947 12 days ago |
12-63015 12 days ago |
60-15232 60 days |
| 39231 |
mbkybky author:mbkybky |
chore(RingTheory/PicardGroup): drop `StrongRankCondition` assumptions in two lemmas |
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
3/6 |
Mathlib/RingTheory/PicardGroup.lean |
1 |
1 |
['github-actions'] |
nobody |
12-51995 12 days ago |
17-71361 17 days ago |
17-80520 17 days |
| 39504 |
WenrongZou author:WenrongZou |
feat(MvPowerSeries/Ideal): kernel of map equals map `C` of kernel |
In this PR, we prove that given a ring homomorphism f, suppose that kernel of f is finitely generated, then kernel of map equals map `C` of kernel. (See `ker_map_of_FG`).
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
87/0 |
Mathlib.lean,Mathlib/RingTheory/MvPowerSeries/Ideal.lean |
2 |
4 |
['CoolRmal', 'WenrongZou', 'github-actions'] |
nobody |
12-42798 12 days ago |
12-53115 12 days ago |
12-53184 12 days |
| 37848 |
rwst author:rwst |
feat(RingTheory/PowerSeries/Log): log and exp as inverses |
This adds the lemmas `exp_subst_log` and `log_subst_exp_sub_one`, together with two helpers needed for the proofs.
Note: I'm using Claude + Opus for supervised formalization tasks. Claude has no permission to use git on my machine.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
LLM-generated
|
88/0 |
Mathlib/RingTheory/PowerSeries/Log.lean,Mathlib/RingTheory/PowerSeries/Substitution.lean |
2 |
10 |
['chrisflav', 'github-actions', 'rwst'] |
chrisflav assignee:chrisflav |
12-29197 12 days ago |
18-39326 18 days ago |
49-21571 49 days |
| 39514 |
SnirBroshi author:SnirBroshi |
chore(RingTheory/Polynomial/Basic): golf `degreeLTEquiv` |
Also extracts the `monomial i a ∈ degreeLT R n` proof to a lemma.
---
The semicolons might be a bit excessive, let me know if so.
Also the `right_inv` proof is slower than the previous version, so maybe it should be reverted, but the rest is fine.
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
11/32 |
Mathlib/RingTheory/Polynomial/Basic.lean |
1 |
1 |
['github-actions'] |
nobody |
12-22596 12 days ago |
12-22882 12 days ago |
12-23059 12 days |
| 36954 |
FMLJohn author:FMLJohn |
feat(Topology/ClosedBases): `TopologicalSpace.IsClosedBasis` and `TopologicalSpace.IsClosedSubbasis s` |
In this pull request, I have defined closed bases and closed subbases of topologies, and proved some basic properties of them.
## Main definitions
* `TopologicalSpace.IsClosedBasis s`: A closed basis of a topological space `α` is a collection of closed sets `s : Set (Set α)` such that every closed subset of `α` can be written as an intersection of elements of `s`.
---
[](https://gitpod.io/from-referrer/) |
t-topology |
117/0 |
Mathlib.lean,Mathlib/Topology/Bases.lean,Mathlib/Topology/ClosedBases.lean |
3 |
19 |
['github-actions', 'scholzhannah'] |
urkud assignee:urkud |
12-22162 12 days ago |
36-48917 36 days ago |
65-51012 65 days |
| 38916 |
yuanyi-350 author:yuanyi-350 |
chore(CategoryTheory/CatCommSq): remove an erw |
- rewrites `hInv_hInv` by using `conv_rhs` with `iso_hom_naturality`
- removes the `rw`/`erw` pair around `Functor.comp_map`
Extracted from #38415
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
|
3/2 |
Mathlib/CategoryTheory/CatCommSq.lean |
1 |
2 |
['github-actions', 'loefflerd'] |
nobody |
12-21350 12 days ago |
25-52874 25 days ago |
25-52643 25 days |
| 26479 |
thefundamentaltheor3m author:thefundamentaltheor3m |
feat(Analysis/Complex/CauchyIntegral): Cauchy–Goursat for Unbounded Rectangles |
In this PR, we prove versions of the Cauchy-Goursat theorem where the contours in question are rectangular and unbounded (ie, where the contours look like the $\bigsqcup$ symbol). I am not sure if I have formalised these in the best way, or if `Analysis.Complex.CauchyIntegral` is the best place for them (it might be prudent to reorganise the file into multiple files at some point), but I believe this is a useful result. Suggestions welcome.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-analysis
sphere-packing
|
219/0 |
Mathlib/Analysis/Complex/CauchyIntegral.lean |
1 |
7 |
['github-actions', 'j-loreaux', 'loefflerd', 'mathlib4-merge-conflict-bot', 'thefundamentaltheor3m', 'wwylele'] |
urkud assignee:urkud |
11-75151 11 days ago |
11-75151 11 days ago |
45-86142 45 days |
| 39183 |
yuanyi-350 author:yuanyi-350 |
refactor(Analysis): golf `Mathlib/Analysis/Complex/Exponential` |
- shortens the reindexing step in `norm_exp_sub_sum_le_norm_mul_exp` by switching from `sum_bij` to `sum_Ico_eq_sum_range` with `simp`
Extracted from #37968
[](https://gitpod.io/from-referrer/) |
codex
t-analysis
LLM-generated
maintainer-merge
|
8/23 |
Mathlib/Analysis/Complex/Exponential.lean |
1 |
4 |
['Komyyy', 'github-actions', 'yuanyi-350'] |
urkud assignee:urkud |
11-72644 11 days ago |
11-72832 11 days ago |
18-54209 18 days |
| 35122 |
Marygold-Dusk author:Marygold-Dusk |
feat: define C^n submersions |
This PR defines submersions between C^n manifolds. In the infinite-dimensional setting, submersions are defined via local normal forms rather than surjectivity of the mfderiv. A map f is a submersion at x if, in suitable charts around x and f x, it has the form (u, v) ↦ u after identifying the model space with a product.
We prove a few basic properties:
- being a submersion is a local property,
- products of submersions are submersions,
- the set of submersed points is open
Future PRs will prove that submersions are C^n and deduce equivalence with the standard definition in finite dimensions. From the path towards the regular value theorem.
This file was developed under the supervision of Michael Rothgang.
Co-authored-by: Michael Rothgang
---
Most of the design is analogues to immersions.
|
t-differential-geometry
new-contributor
|
642/0 |
Mathlib.lean,Mathlib/Geometry/Manifold/Submersion.lean,docs/references.bib |
3 |
54 |
['Marygold-Dusk', 'chrisflav', 'github-actions', 'grunweg'] |
PatrickMassot and grunweg assignee:grunweg assignee:PatrickMassot |
11-63339 11 days ago |
11-63339 11 days ago |
55-83642 55 days |
| 37624 |
IvanRenison author:IvanRenison |
feat(Combinatorics/SimpleGraph/Maps): add theorems about composition |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
maintainer-merge
|
32/5 |
Mathlib/Combinatorics/SimpleGraph/Ends/Defs.lean,Mathlib/Combinatorics/SimpleGraph/Maps.lean |
2 |
11 |
['IvanRenison', 'YaelDillies', 'github-actions'] |
nobody |
11-55975 11 days ago |
13-24164 13 days ago |
54-60727 54 days |
| 39370 |
fpvandoorn author:fpvandoorn |
feat: add specialized grind sets |
This adds two grind attributes for specialized tactics. See module doc for more information and motivation. This PR does not tag any lemmas yet.
[Zulip thread](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/small.20specialized.20grind.20sets/with/595132109)
---
[](https://gitpod.io/from-referrer/)
|
t-meta |
113/0 |
Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/Common.lean,Mathlib/Tactic/GrindAttrs.lean |
4 |
5 |
['chenson2018', 'fpvandoorn', 'github-actions'] |
dwrensha assignee:dwrensha |
11-37635 11 days ago |
15-36311 15 days ago |
15-36080 15 days |
| 39269 |
godofecht author:godofecht |
feat(Algebra/Spectrum): add the second resolvent identity |
Adds `spectrum.resolvent_sub_resolvent`:
For `a b : A` in an `R`-algebra and `r` in the resolvent set of both,
`resolvent a r - resolvent b r = resolvent a r * (a - b) * resolvent b r`.
Companion to `spectrum.resolvent_eq`. |
t-algebra
new-contributor
label:t-algebra$ |
15/0 |
Mathlib/Algebra/Algebra/Spectrum/Basic.lean |
1 |
3 |
['github-actions', 'wwylele'] |
nobody |
11-33133 11 days ago |
17-21298 17 days ago |
17-21067 17 days |
| 39366 |
akiezun author:akiezun |
feat(Data/Nat): add prime divisibility for ascFactorial and choose |
Adds two prime-divisibility lemmas for natural-number factorial/binomial APIs.
The first characterizes when a prime divides an ascending factorial:
`Nat.Prime.dvd_ascFactorial_iff`.
The second applies this to binomial coefficients:
`Nat.Prime.dvd_choose_add_sub_one_iff`, using
`Nat.ascFactorial_eq_factorial_mul_choose'` and cancellation of the `n!` factor
when `n < p`.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
large-import
|
46/0 |
Mathlib.lean,Mathlib/Data/Nat/Choose/Consecutive.lean,Mathlib/Data/Nat/Factorial/BigOperators.lean |
3 |
9 |
['SnirBroshi', 'akiezun', 'github-actions', 'wwylele'] |
nobody |
11-25680 11 days ago |
11-27721 11 days ago |
15-37869 15 days |
| 39549 |
Hagb author:Hagb |
feat(Order/RelIso/Basic): `swap`s and `compl`s are `Equiv`s |
---
[](https://gitpod.io/from-referrer/)
|
t-order |
13/8 |
Mathlib/Order/RelIso/Basic.lean |
1 |
3 |
['Hagb', 'github-actions', 'leanprover-radar'] |
nobody |
11-18016 11 days ago |
11-20457 11 days ago |
11-20226 11 days |
| 39555 |
b-mehta author:b-mehta |
feat(Data/Finset/Image): relate images with nontriviality |
---
[](https://gitpod.io/from-referrer/)
|
t-data |
20/0 |
Mathlib/Data/Finset/Image.lean |
1 |
1 |
['github-actions'] |
nobody |
11-11556 11 days ago |
11-11634 11 days ago |
11-11403 11 days |
| 39098 |
BoltonBailey author:BoltonBailey |
chore(Data/Vector): add `grind` to cons lemmas |
This PR affects `List.Vector.head_cons` and `List.Vector.tail_cons`. It moves the simp attribute assignment of these lemmas to the lemma declarations and also applies the `grind =` attribute.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
2/2 |
Mathlib/Data/Vector/Basic.lean,Mathlib/Data/Vector/Defs.lean |
2 |
4 |
['BoltonBailey', 'github-actions', 'leanprover-radar'] |
nobody |
11-4678 11 days ago |
11-4752 11 days ago |
20-18151 20 days |
| 29744 |
espottesmith author:espottesmith |
feat(Combinatorics): define directed hypergraphs |
This PR defines directed hypergraphs:
```
@[ext]
structure DiHypergraph (α : Type*) where
/-- The vertex set -/
vertexSet : Set α
/-- The edge set -/
edgeSet : Set ((Set α) × (Set α))
/-- Each edge is a pair (s, d), where s ⊆ vertexSet and d ⊆ vertexSet -/
edge_src_dst_isSubset_vertexSet' : ∀ ⦃e⦄, e ∈ edgeSet → e.1 ⊆ vertexSet ∧ e.2 ⊆ vertexSet
```
Additional definitions:
- tail/head stars and negative/positive stars
- some special cases (B-Graph, F-Graph, BF-Graph, and what I'm calling a "non-endless" dihypergraph, where neither the source/tail nor the destination/head are empty)
- Vertex and (hyper)edge adjacency
- isolated vertices
- empty and nonempty dihypergraphs
The design employed here is based off of #28613, but this PR does not depend on that one.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
398/0 |
Mathlib.lean,Mathlib/Combinatorics/DiHypergraph/Basic.lean |
2 |
4 |
['b-mehta', 'espottesmith', 'github-actions', 'mathlib4-merge-conflict-bot'] |
nobody |
11-2543 11 days ago |
56-58328 56 days ago |
114-41564 114 days |
| 33928 |
jsm28 author:jsm28 |
feat(Combinatorics/Tiling/TileSet): indexed families of tiles |
Define the type `TileSet` for indexed families of tiles (in a discrete context), and some associated definitions (including `symmetryGroup`) and API lemmas.
`TileSet` can be used for tilings of the whole space; for tilings of part of the space; for patches of tiles (extracted from a tiling by considering tiles meeting some set of points, or considered on their own without extracting from a tiling); for multiple tilings (covering the space more than once). In particular, the fact that people study multiple tilings provides a clear justification for using indexed families rather than sets of tiles, and basic definitions and API lemmas generally work for all these different uses of `TileSet` (sometimes with weak constraints such as tiles being finite, nonempty and only having finitely many tiles meeting any point of the space).
Definitions for saying e.g. "this `TileSet` is a tiling of the whole space" are to be included in subsequent files in subsequent PRs.
From AperiodicMonotilesLean.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
460/0 |
Mathlib.lean,Mathlib/Combinatorics/Tiling/TileSet.lean |
2 |
23 |
['Parcly-Taxel', 'b-mehta', 'eric-wieser', 'github-actions', 'jsm28', 'vihdzp'] |
nobody |
11-2542 11 days ago |
136-19650 136 days ago |
136-19419 136 days |
| 37443 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Walk/Operations): permutations of support |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
maintainer-merge
|
17/0 |
Mathlib/Combinatorics/SimpleGraph/Paths.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Operations.lean |
2 |
6 |
['YaelDillies', 'github-actions', 'mathlib-merge-conflicts'] |
b-mehta assignee:b-mehta |
11-1077 11 days ago |
18-60335 18 days ago |
58-45380 58 days |
| 39027 |
fpvandoorn author:fpvandoorn |
feat: delaborators for inequalities in big operators |
`∏ i < n, f i` was already accepted as valid syntax, but this PR now also prints appropriate sums/products using this notation.
---
[Zulip discussion](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/missing.20delaborator.20for.20finsum)
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-meta
label:t-algebra$ |
132/49 |
Mathlib/Algebra/BigOperators/Group/Finset/Defs.lean,MathlibTest/BigOps.lean |
2 |
2 |
['fpvandoorn', 'github-actions'] |
kim-em assignee:kim-em |
11-1072 11 days ago |
11-37869 11 days ago |
11-48241 11 days |
| 38092 |
SnirBroshi author:SnirBroshi |
chore(Order/Defs/Unbundled): deprecate `def Symmetric` in favor of `class Std.Symm` |
---
[Mathlib's `def Symmetric`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Order/Defs/Unbundled.html#Symmetric)
[Core's `class Std.Symm`](https://leanprover-community.github.io/mathlib4_docs/Init/Core.html#Std.Symm)
[Zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Relation.20properties.20duplication/near/544638270)
[](https://gitpod.io/from-referrer/)
|
t-order
maintainer-merge
|
465/408 |
Archive/Wiedijk100Theorems/FriendshipGraphs.lean,Archive/Wiedijk100Theorems/Konigsberg.lean,Counterexamples/HeawoodUnitDistance.lean,Mathlib/Algebra/BigOperators/Group/List/Lemmas.lean,Mathlib/Algebra/Divisibility/Units.lean,Mathlib/Algebra/Group/Basic.lean,Mathlib/Analysis/BoxIntegral/Partition/Basic.lean,Mathlib/Analysis/BoxIntegral/Partition/Split.lean,Mathlib/Analysis/InnerProductSpace/Orthogonal.lean,Mathlib/Analysis/Normed/Operator/Compact/FredholmAlternative.lean,Mathlib/CategoryTheory/Abelian/Pseudoelements.lean,Mathlib/CategoryTheory/IsConnected.lean,Mathlib/CategoryTheory/Limits/Final.lean,Mathlib/CategoryTheory/Limits/IsConnected.lean,Mathlib/Combinatorics/Additive/ErdosGinzburgZiv.lean,Mathlib/Combinatorics/Digraph/Orientation.lean,Mathlib/Combinatorics/Graph/Basic.lean,Mathlib/Combinatorics/Graph/Delete.lean,Mathlib/Combinatorics/Graph/Lattice.lean,Mathlib/Combinatorics/Graph/Maps.lean,Mathlib/Combinatorics/SimpleGraph/AdjMatrix.lean,Mathlib/Combinatorics/SimpleGraph/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Combinatorics/SimpleGraph/Circulant.lean,Mathlib/Combinatorics/SimpleGraph/Clique.lean,Mathlib/Combinatorics/SimpleGraph/CompleteMultipartite.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Dart.lean,Mathlib/Combinatorics/SimpleGraph/Density.lean,Mathlib/Combinatorics/SimpleGraph/Hall.lean,Mathlib/Combinatorics/SimpleGraph/Hasse.lean,Mathlib/Combinatorics/SimpleGraph/LineGraph.lean,Mathlib/Combinatorics/SimpleGraph/Maps.lean,Mathlib/Combinatorics/SimpleGraph/Operations.lean,Mathlib/Combinatorics/SimpleGraph/Prod.lean,Mathlib/Combinatorics/SimpleGraph/Regularity/Uniform.lean,Mathlib/Combinatorics/SimpleGraph/Subgraph.lean,Mathlib/Combinatorics/SimpleGraph/Sum.lean,Mathlib/Combinatorics/SimpleGraph/Triangle/Tripartite.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Operations.lean,Mathlib/Data/Finset/Pairwise.lean,Mathlib/Data/Finsupp/BigOperators.lean,Mathlib/Data/List/Pairwise.lean,Mathlib/Data/List/Sigma.lean,Mathlib/Data/Multiset/Bind.lean,Mathlib/Data/Multiset/Defs.lean,Mathlib/Data/Multiset/Pairwise.lean,Mathlib/Data/Multiset/Replicate.lean,Mathlib/Data/Nat/GCD/Basic.lean,Mathlib/Data/Rel/Separated.lean,Mathlib/Data/Seq/Computation.lean,Mathlib/Data/Set/Pairwise/Basic.lean,Mathlib/Data/Set/Pairwise/List.lean,Mathlib/Data/Sym/Sym2.lean,Mathlib/Data/WSeq/Relation.lean,Mathlib/GroupTheory/Perm/Cycle/Factors.lean,Mathlib/GroupTheory/Perm/Cycle/Type.lean,Mathlib/GroupTheory/Perm/Support.lean,Mathlib/Logic/Function/Basic.lean,Mathlib/Logic/Relation.lean,Mathlib/MeasureTheory/Measure/AEDisjoint.lean,Mathlib/MeasureTheory/Measure/NullMeasurable.lean,Mathlib/ModelTheory/Graph.lean,Mathlib/ModelTheory/Semantics.lean,Mathlib/NumberTheory/ArithmeticFunction/Defs.lean,Mathlib/Order/Antichain.lean,Mathlib/Order/Defs/Unbundled.lean,Mathlib/Order/Disjoint.lean,Mathlib/Order/Lattice.lean,Mathlib/Order/Preorder/Chain.lean,Mathlib/Order/PropInstances.lean,Mathlib/RingTheory/Coprime/Ideal.lean,Mathlib/RingTheory/Radical/Basic.lean,Mathlib/Topology/CWComplex/Classical/Graph.lean,Mathlib/Topology/CompactOpen.lean,Mathlib/Topology/Connected/Clopen.lean,Mathlib/Topology/MetricSpace/MetricSeparated.lean,Mathlib/Topology/Separation/Basic.lean,Mathlib/Topology/Separation/GDelta.lean |
80 |
8 |
['SnirBroshi', 'dagurtomas', 'github-actions', 'leanprover-radar', 'mathlib-merge-conflicts'] |
nobody |
10-77355 10 days ago |
10-77394 10 days ago |
42-63292 42 days |
| 39558 |
b-mehta author:b-mehta |
feat(Data/Finset/Prod): count the number of ordered pairs in a set |
These proofs were written a while ago, so they may be golfable
---
[](https://gitpod.io/from-referrer/)
|
t-data |
21/0 |
Mathlib/Data/Finset/Prod.lean |
1 |
2 |
['github-actions', 'plp127'] |
nobody |
10-68074 10 days ago |
11-9029 11 days ago |
11-8798 11 days |
| 38409 |
chrisflav author:chrisflav |
feat(RingTheory): totally split algebras over a field |
We show that for a totally split algebra over a field, the `k`-rational points are in bijection with the prime spectrum. We also show that an étale algebra over a separably closed field is totally split.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
large-import
|
123/2 |
Mathlib/Algebra/Algebra/Pi.lean,Mathlib/FieldTheory/IsSepClosed.lean,Mathlib/RingTheory/Artinian/Module.lean,Mathlib/RingTheory/Etale/Basic.lean,Mathlib/RingTheory/Etale/Field.lean,Mathlib/RingTheory/TotallySplit.lean |
6 |
2 |
['github-actions', 'mathlib-merge-conflicts'] |
mariainesdff assignee:mariainesdff |
10-46392 10 days ago |
10-46469 10 days ago |
35-4148 35 days |
| 38906 |
lua-vr author:lua-vr |
feat(ConditionallyCompleteLattice/Indexed): add binary versions of lemmas |
Add binary versions of some of the lemmas. Those are useful when the domain is indexed over the members of a set.
From the Carleson project.
---
[](https://gitpod.io/from-referrer/)
|
t-order
carleson
|
21/5 |
Mathlib/Order/ConditionallyCompleteLattice/Indexed.lean |
1 |
19 |
['JovanGerb', 'SnirBroshi', 'github-actions', 'grunweg', 'lua-vr', 'mathlib-merge-conflicts'] |
nobody |
10-40600 10 days ago |
10-40665 10 days ago |
20-14347 20 days |
| 39567 |
AlexBrodbelt author:AlexBrodbelt |
feat(Mathlib/Data/Finite/Option): option type is finite iff type is finite |
Option type is finite if and only if the type is finite.
This is an intermediate result to proving that if the `GroupWithZero` is (in)finite then the `Units` are (in)finite.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
|
25/0 |
Mathlib.lean,Mathlib/Data/Finite/Option.lean |
2 |
11 |
['AlexBrodbelt', 'github-actions', 'plp127', 'themathqueen'] |
nobody |
10-40215 10 days ago |
10-56266 10 days ago |
10-56649 10 days |
| 37350 |
aditya-ramabadran author:aditya-ramabadran |
feat(Analysis/Distribution): define canonical maps between Schwartz/test functions, distributions/tempered distributions |
Defines these canonical maps: (1) continuous linear map from $\mathcal D$ to $\mathcal S$, and (2) induced (linear) restriction map from $\mathcal S'$ to $\mathcal D'$, as assigned by @ADedecker.
---
Put in a separate file since Distribution.lean only imports TestFunction right now and I thought it was cleaner to do in a new bridge file with both the maps. Open to changing this though.
* Made use of #36445 (proved first map locally on fixed support spaces first by local seminorm estimates, then used limitCLM)
* Needed a real to complex bridge `TestFunction.ToComplexSchwartzMap` since distributions are defined on real-valued test functions but tempered distributions in mathlib are defined on complex-valued Schwartz functions
* Induced map $\mathcal S'(E,F) \to \mathcal D'(Ω,F)$ is $\mathbb C$-linear
The main important defs are `ContDiffMapSupportedIn.toSchwartzMapCLM` which is the local fixed-support part, then `TestFunction.toSchwartzMapCLM` (where the continuity uses limitCLM to glue the local continuous linear maps on each $\mathcal D_K$), and `TemperedDistribution.toDistributionLM` which is the linear map from tempered distributions to ordinary distributions.
Tested with `lake env lean Mathlib/Analysis/Distribution/TestFunctionSchwartz.lean`
[](https://gitpod.io/from-referrer/)
|
t-analysis
new-contributor
|
225/0 |
Mathlib.lean,Mathlib/Analysis/Distribution/TestFunctionSchwartz.lean |
2 |
24 |
['aditya-ramabadran', 'github-actions', 'j-loreaux'] |
ADedecker and mcdoll assignee:mcdoll assignee:ADedecker |
10-32174 10 days ago |
19-37348 19 days ago |
51-37413 51 days |
| 39585 |
chrisflav author:chrisflav |
chore(RingTheory): add `rfl` lemmas for `Ideal.quotientInfRingEquivPiQuotient` |
From Pi1.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
11/0 |
Mathlib/RingTheory/Ideal/Quotient/Operations.lean |
1 |
1 |
['github-actions'] |
nobody |
10-31238 10 days ago |
10-31321 10 days ago |
10-31090 10 days |
| 39494 |
Hagb author:Hagb |
chore(Data/Finsupp/MonomialOrder): rename fields of `MonomialOrder` to match naming conventions |
Moves:
- MonomialOrder.acm -> MonomialOrder.addCommMonoid_syn
- MonomialOrder.lo -> MonomialOrder.linearOrder_syn
- MonomialOrder.iocam -> MonomialOrder.isOrderedCancelAddMonoid_syn
- MonomialOrder.wf -> MonomialOrder.wellFoundedLT_syn
---
See https://github.com/leanprover-community/mathlib4/pull/32829#discussion_r2716534558.
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
15/6 |
Mathlib/Data/Finsupp/MonomialOrder.lean,Mathlib/RingTheory/MvPolynomial/Groebner.lean |
2 |
1 |
['github-actions'] |
nobody |
10-28310 10 days ago |
12-80000 12 days ago |
12-80296 12 days |
| 39591 |
plp127 author:plp127 |
feat: `Equiv.symm_trans` |
Add theorem `Equiv.symm_trans`, which says `(f.trans g).symm = g.symm.trans f.symm`. See [Zulip](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/.60Equiv.2Esymm_trans.60/near/596266434).
---
[](https://gitpod.io/from-referrer/)
|
easy
t-logic
|
2/0 |
Mathlib/Logic/Equiv/Defs.lean |
1 |
1 |
['github-actions'] |
nobody |
10-20562 10 days ago |
10-20657 10 days ago |
10-20426 10 days |
| 34361 |
grunweg author:grunweg |
chore: rename comp' to fun_comp a few more times; use to_fun to autog… |
…enerate
--------
- [x] depends on: #34257 (then this PR can be done the proper way)
---
[](https://gitpod.io/from-referrer/)
|
t-analysis |
19/42 |
Mathlib/Analysis/Analytic/Composition.lean,Mathlib/Analysis/Calculus/DifferentialForm/Basic.lean,Mathlib/Analysis/Calculus/FDeriv/Comp.lean,Mathlib/Analysis/Calculus/VectorField.lean,Mathlib/Analysis/Meromorphic/Basic.lean |
5 |
10 |
['JovanGerb', 'github-actions', 'grunweg', 'mathlib-dependent-issues'] |
j-loreaux assignee:j-loreaux |
10-1009 10 days ago |
10-15287 10 days ago |
10-60522 10 days |
| 34713 |
dennj author:dennj |
feat(Probability/Markov): stationary distributions for stochastic matrices |
This PR proves that every row-stochastic matrix on a finite nonempty
state space has a stationary distribution in the standard simplex.
Main additions to `Mathlib/Probability/Markov/Stationary.lean`:
- `IsStationary`: A distribution μ is stationary for matrix P if μ ᵥ* P = μ
- `cesaroAverage`: Cesàro average of iterates of a vector under a matrix
- `Matrix.rowStochastic.exists_stationary_distribution`: existence theorem
The proof uses Cesàro averaging: start with uniform distribution, form
averages, extract convergent subsequence by compactness, show limit is
stationary via L¹ non-expansiveness.
Also adds `vecMul_mem_stdSimplex` to `Stochastic.lean`: multiplying a
probability vector by a row-stochastic matrix preserves simplex membership.
This is human-made PR with AI help in golfing proof and documenting the code. |
new-contributor
t-measure-probability
|
166/0 |
Mathlib.lean,Mathlib/LinearAlgebra/Matrix/Stochastic.lean,Mathlib/Probability/Markov/Stationary.lean |
3 |
17 |
['EtienneC30', 'dennj', 'dupuisf', 'github-actions', 'grunweg', 'j-loreaux', 'mathlib-merge-conflicts', 'riccardobrasca'] |
kex-y assignee:kex-y |
10-1008 10 days ago |
33-9462 33 days ago |
43-42244 43 days |
| 35619 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Clique): intersection and union of cliques |
Plus a couple of lemmas.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
maintainer-merge
|
45/14 |
Mathlib/Combinatorics/SimpleGraph/Clique.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/VertexColoring.lean,Mathlib/Data/Set/Pairwise/Basic.lean |
3 |
13 |
['SnirBroshi', 'YaelDillies', 'github-actions'] |
b-mehta assignee:b-mehta |
10-1007 10 days ago |
36-30297 36 days ago |
58-6091 58 days |
| 38014 |
cduenasnavarro author:cduenasnavarro |
feat(InformationTheory): linear codes over finite fields and minimum distance properties |
Define linear codes over a finite field `F` as finite-dimensional subspaces of `Fin n → F`,
together with their minimum Hamming distance.
Main definitions:
* `LinearCode`
* `minDist`
* `LinearCodeWithDist`
* `hammingSphere`
Main results:
* `minDist_eq_sInf_pairwiseDist`: characterisation of the minimum distance via pairwise distances
* `disjoint_spheres`: Hamming spheres of radius `t` around distinct codewords are disjoint
if `2 * t < d`
Pending:
* Choosing an adequate book reference
---
[](https://gitpod.io/from-referrer/)
|
t-measure-probability
new-contributor
|
181/0 |
Mathlib.lean,Mathlib/InformationTheory/Coding/LinearCode.lean |
2 |
37 |
['cduenasnavarro', 'github-actions', 'linesthatinterlace', 'rkirov', 'vihdzp', 'wwylele'] |
kex-y assignee:kex-y |
10-1004 10 days ago |
46-20485 46 days ago |
46-21017 46 days |
| 38055 |
felixpernegger author:felixpernegger |
feat(Topology/EMetricSpace): add r-variation |
Redoing #37007 (I had accidently deleted my fork which nuked the PR).
See https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/p-variation for discussion.
---
[](https://gitpod.io/from-referrer/)
|
t-topology
t-analysis
|
408/0 |
Mathlib.lean,Mathlib/Topology/EMetricSpace/RVariation.lean |
2 |
2 |
['felixpernegger', 'github-actions'] |
urkud assignee:urkud |
10-1003 10 days ago |
43-59522 43 days ago |
43-59685 43 days |
| 38716 |
YaelDillies author:YaelDillies |
feat(Algebra/Order): `NNRat.cast_sub` |
From AddCombi
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
large-import
label:t-algebra$ |
29/22 |
Mathlib/Algebra/Order/Field/Rat.lean,Mathlib/Algebra/Order/Ring/Rat.lean,Mathlib/Combinatorics/SetFamily/LYM.lean,Mathlib/Data/Finset/Density.lean,Mathlib/Data/NNRat/Defs.lean,Mathlib/Data/NNRat/Floor.lean,Mathlib/Data/NNRat/Order.lean,Mathlib/Data/Rat/Star.lean,Mathlib/RingTheory/Binomial.lean,Mathlib/Topology/Instances/Rat.lean |
10 |
1 |
['github-actions'] |
themathqueen assignee:themathqueen |
10-1002 10 days ago |
28-67257 28 days ago |
28-71409 28 days |
| 38974 |
Brian-Nugent author:Brian-Nugent |
chore: fix documentation of `LocallyQuasiFinite` |
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-geometry
easy
|
6/5 |
Mathlib/AlgebraicGeometry/Morphisms/QuasiFinite.lean |
1 |
1 |
['github-actions'] |
alreadydone assignee:alreadydone |
10-1001 10 days ago |
24-13674 24 days ago |
24-13443 24 days |
| 39172 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Function/StronglyMeasurable/Basic` |
- refactors `Mathlib/MeasureTheory/Function/StronglyMeasurable/Basic` by simplifying `stronglyMeasurable_in_set` and `stronglyMeasurable_of_measurableSpace_le_on`
Extracted from #38104
[](https://gitpod.io/from-referrer/)
|
codex
LLM-generated
t-measure-probability
|
16/42 |
Mathlib/MeasureTheory/Function/StronglyMeasurable/Basic.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
kex-y assignee:kex-y |
10-999 10 days ago |
18-62829 18 days ago |
18-62598 18 days |
| 39384 |
EngelsVon author:EngelsVon |
feat(Analysis/Calculus/DifferentialForm): Stokes' theorem on rectangular boxes |
## Summary
This PR proves the generalized Stokes theorem for differential forms on rectangular boxes $[a, b] \subset \mathbb{R}^{m+1}$.
The proof strategy is:
1. Extract the `i`-th signed face component `boxFaceComponent ω i` from an `m`-form `ω` — a scalar function whose divergence equals the top-form density of the exterior derivative `dω`.
2. Apply Mathlib's existing divergence theorem for boxes (`integral_divergence_of_hasFDerivAt_off_countable'`).
This gives a genuine proved Stokes formula in the Euclidean setting, complementing the existing infrastructure for differential forms.
## Main definitions
- `DifferentialForm.topFormDensity`: density function of a top-form field
- `DifferentialForm.boxFaceComponent`: the `i`-th signed face component of an `m`-form on `ℝ^(m+1)`
- `DifferentialForm.boxBoundaryIntegral`: the signed boundary integral over `∂[a,b]`
## Main results
- `box_stokes_of_hasFDerivAt`: Stokes' theorem on boxes with pointwise differentiability hypotheses
- `box_stokes_of_contDiff`: a convenient `C¹` formulation
|
t-analysis
new-contributor
|
314/0 |
Mathlib.lean,Mathlib/Analysis/Calculus/DifferentialForm/BoxStokes.lean |
2 |
2 |
['github-actions'] |
j-loreaux assignee:j-loreaux |
10-995 10 days ago |
15-28060 15 days ago |
15-27829 15 days |
| 39389 |
i-love-lean author:i-love-lean |
feat(Analysis/SpecialFunctions): homeomorphism for spherical coordinates |
A few months ago, I noticed that mathlib was missing change of variables to spherical coordinates, which is taught in undergraduate calculus and useful for many 3D integrals. So far, I used `PolarCoord.lean` as reference and implemented a similar homeomorphism for spherical coordinates. There's still a lot of work left to prove an analog of `integral_comp_polarCoord_symm` but for spherical coordinates, so I'm splitting up the work into several PRs. I also fixed a typo in `PolarCoord.lean`. |
t-analysis
new-contributor
|
133/2 |
Mathlib.lean,Mathlib/Analysis/SpecialFunctions/Complex/Arg.lean,Mathlib/Analysis/SpecialFunctions/PolarCoord.lean,Mathlib/Analysis/SpecialFunctions/SphericalCoord.lean |
4 |
4 |
['github-actions', 'i-love-lean', 'wwylele'] |
j-loreaux assignee:j-loreaux |
10-994 10 days ago |
15-19195 15 days ago |
15-19784 15 days |
| 39406 |
roos-j author:roos-j |
feat(Analysis): van der Corput's lemma |
Adds van der Corput's lemma on one-dimensional oscillatory integrals, a standard tool in harmonic analysis.
Co-authored-by: Manasa Praveen
---
From https://github.com/roos-j/lean-oscillatory, see there for future plans
Zulip discussion [#mathlib4 > Oscillatory integrals in Lean](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Oscillatory.20integrals.20in.20Lean/with/584786060)
AI disclosure: The code in this PR was predominantly human-written. gpt-5.5 has helped in the later stages with shortening proofs, golfing and general advice.
|
t-analysis
new-contributor
|
551/0 |
Mathlib.lean,Mathlib/Analysis/OscillatoryIntegrals/VanDerCorput.lean |
2 |
2 |
['github-actions'] |
j-loreaux assignee:j-loreaux |
10-992 10 days ago |
14-65054 14 days ago |
14-65887 14 days |
| 39441 |
Paul-Lez author:Paul-Lez |
feat: small lemma about multilinear power series |
I'm currently working on a PR that connects the `PowerSeries` API to the `FormalMultilinearSeries` API, and in particular constructs a map from `PowerSeries A` to `FormalMultilinearSeries R A A` for any `R`-algebra `A`. This lemma was useful for proving that this map respects composition.
---
[](https://gitpod.io/from-referrer/)
|
t-analysis |
7/0 |
Mathlib/Analysis/Analytic/Composition.lean |
1 |
3 |
['Paul-Lez', 'github-actions', 'grunweg'] |
j-loreaux assignee:j-loreaux |
10-991 10 days ago |
14-12119 14 days ago |
14-11888 14 days |
| 39454 |
SnirBroshi author:SnirBroshi |
feat(Analysis/Convex/Jensen): more forms of Jensen's strict inequality |
Adds iff theorems for Jensen's strict inequality for `<`/`=`, positive/nonnegative weights, and canonical form versions.
---
Note that as established by existing theorems in the file, "canonical" here refers to comparing terms to the center of mass instead of to each other.
[](https://gitpod.io/from-referrer/)
|
t-analysis |
95/13 |
Mathlib/Analysis/Convex/Jensen.lean |
1 |
1 |
['github-actions'] |
j-loreaux assignee:j-loreaux |
10-989 10 days ago |
14-740 14 days ago |
14-509 14 days |
| 38896 |
peabrainiac author:peabrainiac |
feat(Algebra): multiplicative torsors |
Introduce a class `Torsor` for torsors of multiplicative groups, as a multiplicative counterpart to the existing `AddTorsor` for torsors of additive groups.
---
Adopted / migrated from #8608.
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
385/286 |
Mathlib/Algebra/AddTorsor/Basic.lean,Mathlib/Algebra/AddTorsor/Defs.lean,Mathlib/Algebra/Group/Pointwise/Set/Scalar.lean,Mathlib/Algebra/Notation/Defs.lean,Mathlib/Analysis/Convex/Segment.lean,Mathlib/Tactic/Translate/ToAdditive.lean |
6 |
2 |
['github-actions', 'grunweg'] |
nobody |
9-82385 9 days ago |
9-82459 9 days ago |
15-85915 15 days |
| 39547 |
Hagb author:Hagb |
chore(Order/Preorder/Finite): use `@[to_dual]` on lemmas about `{Min,Max}imal{For,}` |
Proofs of other theorems (e.g. in #39427) with dual theorems dependent on these lemmas would benefit from their duality.
---
[](https://gitpod.io/from-referrer/)
|
t-order |
11/25 |
Mathlib/Order/Preorder/Finite.lean |
1 |
4 |
['Hagb', 'github-actions', 'vihdzp'] |
nobody |
9-80620 9 days ago |
11-20878 11 days ago |
11-20647 11 days |
| 39611 |
mbkybky author:mbkybky |
feat(RingTheory): let `B` be a faithfully flat `A`-algebra, then `A` is a local ring if `B` is |
Let `B` be a faithfully flat `A`-algebra, then `A` is a local ring if `B` is.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
13/0 |
Mathlib/RingTheory/Flat/FaithfullyFlat/Algebra.lean |
1 |
1 |
['github-actions'] |
nobody |
9-52049 9 days ago |
9-52132 9 days ago |
9-51901 9 days |
| 39605 |
Qinghev author:Qinghev |
Add docstrings for reversed range telescoping lemmas |
This PR adds docstrings for two existing Finset telescoping lemmas and their additive versions generated by `to_additive`:
* `Finset.prod_range_div'` / `Finset.sum_range_sub'`
* `Finset.eq_prod_range_div` / `Finset.eq_sum_range_sub`
The goal is a small documentation-only contribution that makes the reversed range telescoping API easier to discover from search and hover docs.
Local checks:
* `git diff --check -- Mathlib/Algebra/BigOperators/Group/Finset/Basic.lean`
* Attempted `lake env lean Mathlib/Algebra/BigOperators/Group/Finset/Basic.lean`, but local validation is currently blocked by downloading the `leanprover/lean4:v4.30.0-rc2` toolchain from GitHub timing out/connection-resetting on this machine.
Opened as draft until the toolchain/network check can be completed or CI confirms the documentation-only change.
|
t-algebra
new-contributor
label:t-algebra$ |
8/2 |
Mathlib/Algebra/BigOperators/Group/Finset/Basic.lean |
1 |
2 |
['github-actions'] |
nobody |
9-50497 9 days ago |
9-50497 9 days ago |
9-50266 9 days |
| 39332 |
Michaillus author:Michaillus |
chore(Topology/Spectral): Added two small lemmas |
chore(Topology/Spectral): Added two lemmas
`IsCompact.isClosed_constructibleTopology_of_isOpen`
`IsCompact.isClosed_constructibleTopology_of_isClosed`
---
[](https://gitpod.io/from-referrer/)
|
t-topology
new-contributor
|
12/0 |
Mathlib/Topology/Spectral/ConstructibleTopology.lean |
1 |
7 |
['Michaillus', 'github-actions', 'plp127', 'qawbecrdtey'] |
PatrickMassot assignee:PatrickMassot |
9-46991 9 days ago |
16-15067 16 days ago |
16-14836 16 days |
| 37477 |
kebekus author:kebekus |
feat: canonical decomposition of complex-meromorphic functions on disks |
Establish the Finite Canonical Decomposition of meromorphic functions, where a complex-meromorphic function `f` on a disk is written as a product of an analytic function without zeros and poles, and canonical factors that take only values of norm one on the boundary of the disk.
A future PR will extend this theorem to handle zeros/poles on the boundary of the disk.
---
[](https://gitpod.io/from-referrer/)
|
t-analysis |
354/12 |
Mathlib.lean,Mathlib/Algebra/Order/WithTop/Untop0.lean,Mathlib/Analysis/Complex/CanonicalDecomposition.lean,Mathlib/Analysis/Meromorphic/Divisor.lean,Mathlib/Analysis/Meromorphic/Order.lean,Mathlib/Analysis/Meromorphic/RCLike.lean,Mathlib/Topology/LocallyFinsupp.lean,Mathlib/Topology/MetricSpace/Pseudo/Defs.lean |
8 |
25 |
['github-actions', 'j-loreaux', 'kebekus'] |
j-loreaux assignee:j-loreaux |
9-46592 9 days ago |
9-46592 9 days ago |
57-71932 57 days |
| 38047 |
mbkybky author:mbkybky |
feat(RingTheory/Finiteness/Ideal): `I` is finitely generated if `f(I)` and `I ∩ ker(f)` are finitely generated |
Let `f : R →+* S` be a surjective ring homomorphism, and let `I` be an ideal of `R`. If `f(I)` and `I ∩ ker(f)` are finitely generated ideals, then `I` is also finitely generated.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
10/3 |
Mathlib/RingTheory/Finiteness/Ideal.lean |
1 |
1 |
['github-actions'] |
mattrobball assignee:mattrobball |
9-43835 9 days ago |
18-43427 18 days ago |
44-78251 44 days |
| 39225 |
junodeveloper author:junodeveloper |
feat(SimpleGraph): add no-bridge theorem for even degree graphs |
This PR proves that a finite graph in which every vertex has even degree has no bridge.
It adds:
* `SimpleGraph.not_isBridge_of_even_degree`
The proof argues by contradiction: if an edge is a bridge, delete it and look at the connected component containing one endpoint. In that component, the endpoint has odd degree, while any other odd-degree vertex would contradict the bridge assumption and the even-degree hypothesis. This contradicts the handshaking lemma via the existing odd-degree API.
Local checks:
```bash
lake build Mathlib.Combinatorics.SimpleGraph.Connectivity.EdgeConnectivity
lake exe lint-style Mathlib.Combinatorics.SimpleGraph.Connectivity.EdgeConnectivity
lake exe runLinter Mathlib.Combinatorics.SimpleGraph.Connectivity.EdgeConnectivity
```
## AI usage disclosure
I used OpenClaw/Codex while developing this PR. Much of the Lean proof of `not_isBridge_of_even_degree` was drafted with AI assistance, including API search and proof refactoring. I reviewed the generated code, made edits, ran the local checks above, and understand and take responsibility for the final statement and proof. |
t-combinatorics
new-contributor
large-import
LLM-generated
|
122/0 |
Mathlib/Combinatorics/SimpleGraph/Connectivity/EdgeConnectivity.lean |
1 |
12 |
['Rida-Hamadani', 'SnirBroshi', 'github-actions', 'junodeveloper', 'linesthatinterlace'] |
nobody |
9-41762 9 days ago |
18-11337 18 days ago |
18-11106 18 days |
| 39607 |
TentativeConvert author:TentativeConvert |
feat(Algebra/DirectSum): equivalence between direct sum indexed by ι₁ and double sum indexed by ι₂ and fibres of f : ι₁ → ι₂ |
1. Add variant `equivCongrLeft'` of `equivCongrLeft`, and corresponding `…_apply` lemma.
2. Add `…_of lemmas` for both `equivCongrLeft` and `equivCongrLeft'`.
3. Add `…of lemma` for `sigmaCurry`, i.e. `sigmaCurry_of`.
4. Add `sigmaFiberAddEquiv`: the equivalence between a direct sum indexed by a type `ι₁` and the double sum indexed by a type `ι₂` and the fibres of a map `f : ι₁ → ι₂`. Add two `…_apply` lemmas and an `…_of` lemma.
---
This is supposed to be a first step towards merging the draft PR #39356.
re 1: Mathematically, I don't see why one version should be preferred over the other, but I found the existing `equivCongrLeft` more difficult to work with when the equivalence `h : ι ≃ κ` is naturally given in the opposite direction. (I could not avoid explicit type casts through the equality `h.symm.symm = h` when defining `sigmaFiberAddEquiv` in terms of `equivCongrLeft`.)
Very unsure about the name of `equivCongrLeft'`. (I see that the name `equivCongrLeft` was chosen in analogy with `Equiv.piCongrLeft`. `Equiv.piCongrRight` looks very different, so presumably `equivCongrLeft'` should *not* be called `equivCongrRight`.)
re 4: Very unsure about the naming of the two different `…_apply` lemmas; called them `…_apply` and `…_apply'` for now. The second (`…_apply'`) cannot be a `simp` lemma as it would prevent the first (`…_apply`) from firing.
I've used Claude Opus for understanding error messages and git interaction, but everything is hand coded.
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
66/1 |
Mathlib/Algebra/DirectSum/Basic.lean |
1 |
3 |
['github-actions'] |
nobody |
9-41032 9 days ago |
9-53585 9 days ago |
9-54984 9 days |
| 39624 |
justus-springer author:justus-springer |
feat(Algebra/MvPolynomial/PDeriv): a coefficient formula for `pderiv` |
This formula is useful for defining partial derivatives of multivariate power series, see PR #39626.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
15/0 |
Mathlib/Algebra/MvPolynomial/PDeriv.lean |
1 |
1 |
['github-actions'] |
nobody |
9-31209 9 days ago |
9-31803 9 days ago |
9-31572 9 days |
| 39625 |
justus-springer author:justus-springer |
feat(RingTheory/MvPowerSeries/Trunc): generalize truncation lemmas |
Generalize `coeff_trunc_mul_trunc_eq_coeff_mul` (and its analogs for `truncFinset` and `trunc'`) to allow for different truncation levels for the two arguments. This matches the API for univariate power series, where we already have `PowerSeries.coeff_mul_eq_coeff_trunc_mul_trunc₂`.
This is useful for defining partial derivatives of multivariate power series, see PR #39626.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
39/7 |
Mathlib/RingTheory/MvPowerSeries/Trunc.lean |
1 |
1 |
['github-actions'] |
nobody |
9-31191 9 days ago |
9-31586 9 days ago |
9-31355 9 days |
| 39487 |
ADedecker author:ADedecker |
chore: switch `EqLocus` from `LinearMapClass` to `LinearMap` |
---
Note: this PR was opened at 35000 feet :slightly_smiling_face:
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
18/14 |
Mathlib/Algebra/Algebra/Subalgebra/Basic.lean,Mathlib/Algebra/Module/Submodule/EqLocus.lean,Mathlib/Analysis/InnerProductSpace/MeanErgodic.lean,Mathlib/Topology/Algebra/Module/ContinuousLinearMap/Basic.lean |
4 |
10 |
['ADedecker', 'b-mehta', 'github-actions', 'j-loreaux', 'themathqueen'] |
nobody |
9-14562 9 days ago |
9-56102 9 days ago |
12-27726 12 days |
| 33714 |
idontgetoutmuch author:idontgetoutmuch |
feat(Mathlib/Geometry/Manifold): Riemannian metrics exist II |
Supersedes https://github.com/leanprover-community/mathlib4/pull/33519
---
[](https://gitpod.io/from-referrer/)
|
t-differential-geometry
new-contributor
|
723/0 |
Mathlib.lean,Mathlib/Algebra/BigOperators/Finprod.lean,Mathlib/Geometry/Manifold/ExistsRiemannianMetric.lean,Mathlib/Geometry/Manifold/PartitionOfUnity.lean |
4 |
200 |
['Rida-Hamadani', 'github-actions', 'grunweg', 'idontgetoutmuch'] |
nobody |
9-2541 9 days ago |
40-42092 40 days ago |
85-48844 85 days |
| 39635 |
SnirBroshi author:SnirBroshi |
feat(LinearAlgebra/Eigenspace/Matrix): a scalar is in the spectrum iff it's an eigenvalue |
---
[#Is there code for X? > Matrix eigenvalues: spectrum and mulVec](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Matrix.20eigenvalues.3A.20spectrum.20and.20mulVec/with/596538140)
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
18/0 |
Mathlib/LinearAlgebra/Eigenspace/Matrix.lean |
1 |
1 |
['github-actions'] |
nobody |
9-995 9 days ago |
9-1076 9 days ago |
9-845 9 days |
| 36709 |
kim-em author:kim-em |
feat(DefEqAbuse): suggest minimal @[implicit_reducible] workaround |
This PR extends `#defeq_abuse` to suggest a minimal set of `@[implicit_reducible]` annotations that would make the failing tactic or command succeed with `backward.isDefEq.respectTransparency true`.
When `#defeq_abuse` detects a failure, it now runs a greedy minimisation over semireducible definitions reachable from the goal/command, finding a (possibly non-unique) minimal subset that, when temporarily marked `@[implicit_reducible]`, fixes the issue. The result is reported as an `info` message:
```
info: Workaround: the following @[implicit_reducible] annotations (a possibly non-unique minimal set) would paper over this problem,
but the real issue is likely a leaky instance somewhere.
set_option allowUnsafeReducibility true
attribute [implicit_reducible]
MyPred
```
This is a workaround, not a fix — the real cause is usually a leaky instance (which `#check_instance` from https://github.com/leanprover-community/mathlib4/pull/36706 can diagnose). But it can be useful for quick debugging.
New helpers: `collectCandidates`, `markImplicitReducible`, `withTempImplicitReducible`, `withTempImplicitReducibleCmd`, `suggestAnnotationsTac`, `suggestAnnotationsCmd`, `formatAnnotations`, `logAnnotationSuggestions`.
🤖 Prepared with Claude Code |
t-meta
LLM-generated
|
187/17 |
Mathlib/Tactic/DefEqAbuse.lean,MathlibTest/DefEqAbuse.lean |
2 |
6 |
['github-actions', 'kim-em', 'mathlib-merge-conflicts', 'thorimur'] |
JovanGerb assignee:JovanGerb |
9-961 9 days ago |
31-53381 31 days ago |
48-51361 48 days |
| 38225 |
kim-em author:kim-em |
ci: block merging PRs with large import increases unless reviewed |
This PR makes the existing `large-import` label into a merge gate. PRs that significantly increase transitive imports (>2% for any modified file) are now blocked from merging until a reviewer adds the `allow-large-import` label.
### Why three labels?
Bors's `block_labels` has no conditional logic — if a label is in the list, merge is blocked unconditionally. We need "blocked unless a reviewer has approved", i.e. `large-import ∧ ¬allow-large-import`. Since bors can't express that, we use a derived label:
| Label | Managed by | Purpose |
|---|---|---|
| `large-import` | `build` job (import analysis) | Factual: this PR increases imports |
| `blocked-by-large-import` | `check-large-import` job | Operational: blocks bors |
| `allow-large-import` | Reviewer | Override: reviewer approves the increase |
Each label is managed by exactly one actor, so there is no label-fighting.
### How it works
1. The existing `build` job adds/removes `large-import` based on import analysis (unchanged).
2. A new `check-large-import` job (in the same workflow) waits for `build` to finish, then:
- If `large-import` is present and `allow-large-import` is absent → adds `blocked-by-large-import`
- Otherwise → removes `blocked-by-large-import`
3. `blocked-by-large-import` is added to `block_labels` in `bors.toml`.
When a reviewer adds `allow-large-import`, the `labeled` event re-triggers the workflow. The heavy `build` job is skipped (guarded by `github.event.action != 'labeled'`), but the lightweight `check-large-import` job runs, sees both labels, and removes `blocked-by-large-import`. Bors can now merge.
### Reviewer workflow
The CI failure message tells the reviewer to consider whether the PR could be improved by splitting files, rearranging material, or creating new intermediate files. If the import increase is reasonable, they add `allow-large-import`.
False positives can be reported on the [mathlib4 Zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/large-import.20label).
🤖 Prepared with Claude Code |
CI |
78/2 |
.github/workflows/PR_summary.yml,bors.toml |
2 |
7 |
['SnirBroshi', 'github-actions', 'jcommelin', 'joneugster', 'kim-em'] |
bryangingechen assignee:bryangingechen |
9-957 9 days ago |
39-7293 39 days ago |
39-7680 39 days |
| 38500 |
kebekus author:kebekus |
feat: integral presentation of the proximity function of value distribution theory |
If `f : ℂ → ℂ` is meromorphic, establish a presentation of the proximity function `proximity f ⊤` as iterated circle averages. This statement can be used to compare the proximity- and logarithmic counting functions, and is one of the key ingredients in the proof of Cartan's classic formula for the characteristic function.
This is the first section of a multi-part PR, establishing Cartan's formula.
---
[](https://gitpod.io/from-referrer/)
|
t-analysis |
211/0 |
Mathlib.lean,Mathlib/Analysis/Complex/ValueDistribution/Proximity/IntegralPresentation.lean |
2 |
11 |
['github-actions', 'kebekus', 'wwylele'] |
j-loreaux assignee:j-loreaux |
9-956 9 days ago |
33-72414 33 days ago |
34-66886 34 days |
| 38823 |
matthewjasper author:matthewjasper |
chore(LinearAlgebra/TensorProduct): fix diamond in `AddCommGroup` instance |
The `SMul` instance for tensor products directly used `AddCon.lift`, so wasn't type correct at instance transparency. This caused a diamond with the `AddCommGroup` instance on tensor products because after unfolding some types didn't match, so I've wrapped the sMul function in a semireducible def to prevent this.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
30/23 |
Mathlib/LinearAlgebra/TensorProduct/Basic.lean,Mathlib/LinearAlgebra/TensorProduct/Defs.lean |
2 |
6 |
['dagurtomas', 'github-actions', 'kbuzzard', 'leanprover-radar'] |
themathqueen assignee:themathqueen |
9-955 9 days ago |
28-15352 28 days ago |
28-15121 28 days |
| 39474 |
emlis42 author:emlis42 |
feat(Topology/Separation/Hausdorff): add `Filter.limUnder_congr` |
This PR adds `Filter.limUnder_congr` and some lemmas about `limUnder`.
`Filter.limUnder_congr` allows rewriting `limUnder` expressions using equivalences of convergence behavior, without proving the filters actually converge, allowing convergence proofs to be carried out on more convenient expressions latter. |
t-topology
new-contributor
large-import
|
24/1 |
Mathlib/Order/Filter/AtTopBot/Archimedean.lean,Mathlib/Topology/Separation/Hausdorff.lean |
2 |
2 |
['github-actions'] |
PatrickMassot assignee:PatrickMassot |
9-953 9 days ago |
13-22383 13 days ago |
13-22152 13 days |
| 38483 |
jessealama author:jessealama |
feat(Algebra/BigOperators): add `Antiperiodic.sum_Ico_shift` |
Three lemmas about `Finset` sums of `Function.Antiperiodic` functions: `sum_map_add_right` says that for `f` antiperiodic with antiperiod `c`, summing `f` over a `Finset` shifted by `c` (via `addRightEmbedding c`) negates the sum over the original; `sum_Ico_shift` is the half-open-interval specialization, immediate via `Finset.map_add_right_Ico`; and `sum_Ico_mul_add_sum_Ico_mul_shift_eq_zero` is a bilinear cancellation variant. Spun off from #29713 (Euler-Poincaré formula), where the bilinear form is used. |
t-algebra label:t-algebra$ |
63/0 |
Mathlib.lean,Mathlib/Algebra/BigOperators/Periodic.lean |
2 |
5 |
['github-actions', 'j-loreaux', 'jessealama', 'wwylele'] |
ocfnash assignee:ocfnash |
8-86317 8 days ago |
24-68544 24 days ago |
34-41344 34 days |
| 36376 |
jessealama author:jessealama |
feat(SimpleGraph): hamiltonian cycle from cyclic permutation |
This PR provides `IsHamiltonian.of_perm`, a bridge from `Equiv.Perm.IsCycle` to `SimpleGraph.IsHamiltonian`: if σ is a permutation that is a single cycle with full support on at least 3 elements, and each step `v → σ v` is an edge of `G`, then `G` is Hamiltonian.
### New definitions and lemmas
**`Mathlib/Data/List/Chain.lean`**:
- `IsChain.iterate`: `List.iterate f a n` is a chain under `r` whenever `r a (f a)` holds for all `a`
**`Mathlib/Data/List/Iterate.lean`**:
- `getLast_iterate`: the last element of `List.iterate f a n` is `f^[n - 1] a`
**`Mathlib/Combinatorics/SimpleGraph/Walk/Iterate.lean`** (new file):
- `Walk.iterate`: builds a walk of length `n` from `x` to `f^[n] x` for any function `f` with `G.Adj x (f x)` for all `x`, defined via `Walk.ofSupport`
- `Walk.length_iterate`, `Walk.support_iterate`, `Walk.edges_iterate`: basic API
**`Mathlib/GroupTheory/Perm/Cycle/Basic.lean`**:
- `IsCycleOn.injOn_pow_apply`: the map `n ↦ (f ^ n) a` is injective on `Finset.range #s`
**`Mathlib/GroupTheory/Perm/Cycle/Concrete.lean`**:
- `IsCycleOn.injOn_sym2_pow_apply`: the unordered-pair edge map `k ↦ s((f ^ k) a, (f ^ (k + 1)) a)` is injective on `[0, #s)` when `#s ≠ 2`
- `IsCycleOn.sym2_pow_apply_ne`: edge distinctness for cycle-on permutations — `s((f ^ k) a, (f ^ (k + 1)) a) ≠ s(a, f a)` when `k ≠ 0`, `k < #s`, and `#s ≠ 2`
- `Perm.toList_eq_range_map_pow`: expresses `toList` as a range map over powers
**`Mathlib/Combinatorics/SimpleGraph/Hamiltonian.lean`**:
- `cons_isHamiltonianCycle_iff`: a Hamiltonian path closed by an edge outside its support is a Hamiltonian cycle, and conversely
- `IsHamiltonian.of_perm`: the main theorem
---
- [x] depends on: #36307 |
t-combinatorics
maintainer-merge
|
182/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Hamiltonian.lean,Mathlib/Combinatorics/SimpleGraph/Hamiltonian/Perm.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Iterate.lean,Mathlib/Data/List/Chain.lean,Mathlib/Data/List/Iterate.lean,Mathlib/GroupTheory/Perm/Cycle/Basic.lean,Mathlib/GroupTheory/Perm/Cycle/Concrete.lean |
8 |
78 |
['SnirBroshi', 'YaelDillies', 'github-actions', 'jessealama', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
nobody |
8-83907 8 days ago |
10-68736 10 days ago |
55-1844 55 days |
| 38934 |
YaelDillies author:YaelDillies |
feat(Geometry): convex hull in a `ConvexSpace` |
---
- [x] depends on: #38905
[](https://gitpod.io/from-referrer/)
|
t-convex-geometry |
119/0 |
Mathlib.lean,Mathlib/Geometry/Convex/Hull.lean |
2 |
11 |
['YaelDillies', 'github-actions', 'martinwintermath', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
nobody |
8-53320 8 days ago |
8-53751 8 days ago |
8-54233 8 days |
| 38531 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Paths): `Walk.map` preserves more properties |
Adds some missing theorems about how `Walk.map` behaves with `IsTrail`/`IsPath`/`IsCircuit`/`IsCycle`.
Summary of what we have now, with the 8 new theorems and 2 renames marked:
```
IsTrail.of_map : (p.map f).IsTrail → p.IsTrail -- new
map_isTrail_iff_of_injective : f.Injective → (p.map f).IsTrail ↔ p.IsTrail
IsTrail.map : f.Injective → p.IsTrail → (p.map f).IsTrail -- renamed from map_isTrail_of_injective
IsPath.of_map : (p.map f).IsPath → p.IsPath
map_isPath_iff_of_injective : f.Injective → (p.map f).IsPath ↔ p.IsPath
IsPath.map : f.Injective f → p.IsPath → (p.map f).IsPath -- renamed from map_isPath_of_injective
IsCircuit.of_map : (p.map f).IsCircuit → p.IsCircuit -- new
map_isCircuit_iff_of_injective : f.Injective → (p.map f).IsCircuit ↔ p.IsCircuit -- new
IsCircuit.map : f.Injective → p.IsCircuit → (p.map f).IsCircuit -- new
IsCycle.of_map : (p.map f).IsCycle → p.IsCycle -- new
map_isCycle_iff_of_injective : f.Injective → (p.map f).IsCycle ↔ p.IsCycle
IsCycle.map : f.Injective → p.IsCycle → (p.map f).IsCycle
mapLe_isTrail : G ≤ G' → (p.mapLe h).IsTrail ↔ p.IsTrail
IsTrail.of_mapLe : G ≤ G' → (p.mapLe h).IsTrail → p.IsTrail
IsTrail.mapLe : G ≤ G' → p.IsTrail → (p.mapLe h).IsTrail
mapLe_isPath : G ≤ G' → (p.mapLe h).IsPath ↔ p.IsPath
IsPath.of_mapLe : G ≤ G' → (p.mapLe h).IsPath → p.IsPath
IsPath.mapLe : G ≤ G' → p.IsPath → (p.mapLe h).IsPath
mapLe_isCircuit : G ≤ G' → (p.mapLe h).IsCircuit ↔ p.IsCircuit -- new
IsCircuit.of_mapLe : G ≤ G' → (p.mapLe h).IsCircuit → p.IsCircuit -- new
IsCircuit.mapLe : G ≤ G' → p.IsCircuit → (p.mapLe h).IsCircuit -- new
mapLe_isCycle : G ≤ G' → (p.mapLe h).IsCycle ↔ p.IsCycle
IsCycle.of_mapLe : G ≤ G' → (p.mapLe h).IsCycle → p.IsCycle
IsCycle.mapLe : G ≤ G' → p.IsCycle → (p.mapLe h).IsCycle
```
---
Also golfs `map_isPath_of_injective`/`IsPath.of_map`/`map_isTrail_iff_of_injective`, they don't need induction.
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
47/30 |
Mathlib/Combinatorics/SimpleGraph/Paths.lean |
1 |
1 |
['github-actions'] |
nobody |
8-47228 8 days ago |
34-17842 34 days ago |
34-17611 34 days |
| 39627 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/LapMatrix): 0 is always an eigenvalue |
and the determinant is always zero, plus a few other small lemmas.
---
- [x] depends on: #39642
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
71/15 |
Mathlib/Combinatorics/SimpleGraph/LapMatrix.lean |
1 |
2 |
['github-actions', 'mathlib-dependent-issues'] |
nobody |
8-45343 8 days ago |
8-49813 8 days ago |
9-10892 9 days |
| 39657 |
mcdoll author:mcdoll |
feat(Algebra): add abstract `prod_apply` and `FunLike.coe_prod` |
Follow-up of #37779, where abstract `IsApply` classes were introduced. Now, we can prove a generic `sum_apply` lemma
and in following PRs this will replace specific ones in function spaces.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
25/5 |
Mathlib/Algebra/BigOperators/Pi.lean,Mathlib/Analysis/Calculus/FDeriv/Add.lean,Mathlib/Data/Matrix/PEquiv.lean,Mathlib/LinearAlgebra/Matrix/Polynomial.lean,Mathlib/LinearAlgebra/QuadraticForm/Dual.lean |
5 |
2 |
['github-actions', 'mcdoll'] |
nobody |
8-37563 8 days ago |
8-38167 8 days ago |
8-37936 8 days |
| 38319 |
Zetetic-Dhruv author:Zetetic-Dhruv |
feat(Combinatorics/SetFamily): Assouad's dual VC bound |
Adds the Finset-level form of Assouad's 1983 dual VC bound: if a family
`𝒜 : Finset (Finset α)` has VC dimension at most `d`, then for any
ground set `X : Finset α` the dual family
`{𝒜.filter (· ∋ x) : x ∈ X}` has VC dimension at most `2 ^ (d + 1) - 1`.
New declarations (in `Finset` namespace):
- `dualFamily 𝒜 X`: for each `x ∈ X`, the subfamily `{A ∈ 𝒜 | x ∈ A}`
- `mem_dualFamily` (`@[simp]`): membership characterisation
- `exists_shatters_of_dualFamily_shatters`: Assouad's bitstring-coding lemma
- `vcDim_dualFamily_le`: the headline VC bound
Proof by Assouad's classical bitstring-coding argument. Sits on top of `Finset.shatterer` / `Finset.vcDim` from
`Mathlib.Combinatorics.SetFamily.Shatter`.
References:
- P. Assouad, Densite et dimension, Ann. Inst. Fourier 33(3) (1983), Thm 2.13
- J. Matousek, Lectures on Discrete Geometry, GTM 212, Springer, 2002, Section 10.3 Lemma 10.3.3
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
199/0 |
Mathlib.lean,Mathlib/Combinatorics/SetFamily/DualVC.lean,docs/references.bib |
3 |
37 |
['Shreyas4991', 'YaelDillies', 'Zetetic-Dhruv', 'github-actions'] |
nobody |
8-32928 8 days ago |
20-15161 20 days ago |
36-61979 36 days |
| 37189 |
Brian-Nugent author:Brian-Nugent |
feat(AlgebraicGeometry): The pushforward of a quasi-coherent sheaf between affines is quasi-coherent |
To be more precise, we show that if `AlgebraicGeometry.Scheme.Modules.fromTildeΓ` is an isomorphism then the same holds for the pushforward. This will show that being quasicoherent is stable under pushforward for affine morphisms once it is shown that `AlgebraicGeometry.Scheme.Modules.fromTildeΓ` being an isomorphism is equivalent to being quasicoherent.
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-geometry
maintainer-merge
|
215/6 |
Mathlib/Algebra/Category/ModuleCat/Localization.lean,Mathlib/Algebra/Category/ModuleCat/Sheaf.lean,Mathlib/Algebra/Category/ModuleCat/Sheaf/PushforwardContinuous.lean,Mathlib/Algebra/Module/LocalizedModule/Basic.lean,Mathlib/AlgebraicGeometry/Modules/Sheaf.lean,Mathlib/AlgebraicGeometry/Modules/Tilde.lean,Mathlib/Topology/Sheaves/SheafCondition/Sites.lean |
7 |
49 |
['Brian-Nugent', 'chrisflav', 'github-actions', 'joelriou'] |
adamtopaz and chrisflav assignee:adamtopaz assignee:chrisflav |
8-31400 8 days ago |
9-14085 9 days ago |
43-33132 43 days |
| 39665 |
justus-springer author:justus-springer |
feat(AlgebraicGeometry/AffineSpace): affine space over an integral base is integral |
Prove that `AffineSpace` inherits the properties `IrreducibleSpace`, `IsReduced` and `IsIntegral` from its base.
Also clean up a few variables, that were used very scarcely. These were causing weird issues in these new instances, where they would be automatically included.
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-geometry |
33/12 |
Mathlib/AlgebraicGeometry/AffineSpace.lean |
1 |
1 |
['github-actions'] |
nobody |
8-27481 8 days ago |
8-27562 8 days ago |
8-27331 8 days |
| 36472 |
EtienneC30 author:EtienneC30 |
feat: finite dimensional distribution of Brownian motion |
Define `gaussianProjectiveFamily : (I : Finset ℝ≥0) → Measure (I → ℝ)`. Each `gaussianProjectiveFamily I` is the centered Gaussian measure over `I → ℝ` with covariance matrix given by `brownianCovMatrix I s t := min s t`.
Prove that these measures satisfy `IsProjectiveMeasureFamily`, which means that they can be extended into a measure over `ℝ≥0 → ℝ` thanks to the Kolmogorov's extension theorem (not in Mathlib yet). The obtained measure is a measure over the set of real processes indexed by `ℝ≥0` and is the law of the Brownian motion.
---
- [x] depends on: #36143
[](https://gitpod.io/from-referrer/)
|
brownian
t-measure-probability
large-import
|
236/1 |
Mathlib.lean,Mathlib/MeasureTheory/Function/L2Space.lean,Mathlib/Probability/BrownianMotion/GaussianProjectiveFamily.lean,Mathlib/Probability/Distributions/Gaussian/HasGaussianLaw/Basic.lean,Mathlib/Probability/Moments/Basic.lean |
5 |
5 |
['EtienneC30', 'github-actions', 'mathlib-dependent-issues', 'sgouezel'] |
sgouezel assignee:sgouezel |
8-20627 8 days ago |
8-20594 8 days ago |
74-34114 74 days |
| 39223 |
BryceT233 author:BryceT233 |
feat(RingTheory/Extension): surjectivity and kernel of `Cotangent.map` |
This PR adds `Cotangent.map_surjective_of_comap_eq` and `Cotangent.map_ker_of_surjective`, which are adaptations of the existing lemmas `Ideal.mapCotangent_surjective_of_comap_eq` and `Ideal.mapCotangent_ker_of_surjective` to the cotangent space of extensions. Because `Algebra.Extension.Cotangent` uses a type synonym to define the cotangent space of an extension, the results for `Ideal.mapCotangent` could not be used directly and needed to be restated in terms of `Algebra.Extension.Cotangent.map`.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
32/0 |
Mathlib/RingTheory/Extension/Basic.lean |
1 |
1 |
['github-actions'] |
nobody |
8-12112 8 days ago |
18-13534 18 days ago |
18-13303 18 days |
| 36667 |
NoneMore author:NoneMore |
feat(ModelTheory): add `exClosure` definition for first-order formulas |
Prepare for moving realizations between elementarily equivalent structures.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-logic
|
37/0 |
Mathlib/ModelTheory/Semantics.lean,Mathlib/ModelTheory/Syntax.lean |
2 |
2 |
['github-actions'] |
nobody |
8-2540 8 days ago |
75-73161 75 days ago |
75-72930 75 days |
| 27493 |
themathqueen author:themathqueen |
feat(RingTheory/Coalgebra): define Frobenius algebra |
A Frobenius algebra `A` has the structure of both an algebra and a coalgebra such that:
`(mul ⊗ id) ∘ assoc.symm ∘ (id ⊗ comul) = comul ∘ mul = (id ⊗ mul) ∘ assoc ∘ (comul ⊗ id)`.
In diagrams this law looks like:
It suffices to show that
`(mul ⊗ id) ∘ assoc.symm ∘ (id ⊗ comul) = (id ⊗ mul) ∘ assoc ∘ (comul ⊗ id)`.
---
- [x] depends on: #27567
- [x] depends on: #27569
- [x] depends on: #32245
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
112/0 |
Mathlib.lean,Mathlib/RingTheory/FrobeniusAlgebra.lean |
2 |
25 |
['YaelDillies', 'erdOne', 'github-actions', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot', 'themathqueen'] |
mariainesdff assignee:mariainesdff |
8-1059 8 days ago |
30-14285 30 days ago |
76-78844 76 days |
| 38141 |
Jun2M author:Jun2M |
feat(Order/Partition): Partition induced by symmetric, transitive relation |
We introduce a constructor for Partition from a symmetric, transitive relation, with `copy` function baked into the definition.
Co-authored-by: Peter Nelson
---
[](https://gitpod.io/from-referrer/)
|
t-order |
41/7 |
Mathlib/Order/Partition/Basic.lean |
1 |
1 |
['github-actions'] |
bryangingechen assignee:bryangingechen |
8-1051 8 days ago |
42-85836 42 days ago |
42-85605 42 days |
| 38975 |
ldct author:ldct |
feat(EReal): Add equations for EReal |
Add equational lemmas for the simplifier to simplify `[natural number literal] + ⊤` in `EReal`, and add a test file in `MathlibTest/EReal.lean`.
Without these lemmas, `simp` fails to close many of the goals in `MathlibTest/EReal.lean`. I believe simp should close all of them.
An alternative is to add something like this as a simp lemma, to allow `top_add_of_ne_bot` to make progress, but it's not clear to me that this is desirable as a simp lemma, since it's not equational
```
example {n : ℕ} [n.AtLeastTwo] : (ofNat(n) : EReal) ≠ ⊤ := by
exact Ne.symm (not_eq_of_beq_eq_false rfl)
```
---
[](https://gitpod.io/from-referrer/)
|
t-data |
32/0 |
Mathlib/Data/EReal/Operations.lean,MathlibTest/EReal.lean |
2 |
2 |
['github-actions', 'vihdzp'] |
TwoFX assignee:TwoFX |
8-1047 8 days ago |
24-9729 24 days ago |
24-9498 24 days |
| 39174 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Integral/Asymptotics` |
- refactors `Mathlib/MeasureTheory/Integral/Asymptotics` by simplifying `IsBigO.set_integral_isBigO`
Extracted from #38104
[](https://gitpod.io/from-referrer/)
|
codex
LLM-generated
t-measure-probability
|
6/12 |
Mathlib/MeasureTheory/Integral/Asymptotics.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
kex-y assignee:kex-y |
8-1046 8 days ago |
18-62825 18 days ago |
18-62594 18 days |
| 39175 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Integral/CircleTransform` |
- refactors `Mathlib/MeasureTheory/Integral/CircleTransform` by shortening `circleTransformDeriv_periodic`
Extracted from #38104
[](https://gitpod.io/from-referrer/)
|
codex
LLM-generated
t-measure-probability
|
1/6 |
Mathlib/MeasureTheory/Integral/CircleTransform.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
RemyDegenne assignee:RemyDegenne |
8-1045 8 days ago |
18-62822 18 days ago |
18-62591 18 days |
| 39437 |
ooovi author:ooovi |
feat(Geometry/Convex/ConvexSpace): show that an `AffineMap` `IsAffineMap` |
Show that `Convexity.IsAffineMap` generalises `AffineMap`s between affine spaces.
---
[](https://gitpod.io/from-referrer/)
|
t-convex-geometry |
34/3 |
Mathlib/Geometry/Convex/ConvexSpace/AffineSpace.lean,Mathlib/Geometry/Convex/ConvexSpace/Defs.lean |
2 |
3 |
['github-actions', 'mathlib-merge-conflicts', 'ooovi'] |
nobody |
7-67208 7 days ago |
7-67281 7 days ago |
12-76541 12 days |
| 39575 |
YaelDillies author:YaelDillies |
chore(Data/Finsupp): make `mapDomain_congr` congr |
This makes simp stronger. It particular, it breaks some proofs that relied on simp being weak.
From MeanFourier
---
[](https://gitpod.io/from-referrer/)
|
t-convex-geometry |
29/36 |
Mathlib/Algebra/MvPolynomial/Nilpotent.lean,Mathlib/Data/Finsupp/Basic.lean,Mathlib/Geometry/Convex/ConvexSpace/Defs.lean,Mathlib/LinearAlgebra/Basis/Defs.lean,Mathlib/LinearAlgebra/Finsupp/Pi.lean,Mathlib/LinearAlgebra/Matrix/Basis.lean,Mathlib/NumberTheory/NumberField/EquivReindex.lean,Mathlib/NumberTheory/NumberField/House.lean,Mathlib/RepresentationTheory/Homological/GroupHomology/Functoriality.lean,Mathlib/RepresentationTheory/Intertwining.lean |
10 |
1 |
['github-actions'] |
nobody |
7-61825 7 days ago |
7-61902 7 days ago |
7-71323 7 days |
| 39687 |
TentativeConvert author:TentativeConvert |
feat(Algebra/Group/Submonoid): type class to indicate that supremum in a SubmonoidClass agrees with supremum of submonoids |
Add a type class `SubmonoidClass.IsConcreteSSup` to indicate that the canonical map `.ofClass` from a class `S` of submonoids of `M` to `Submonoid M` preserves suprema.
---
This PR implements the minimal type class assumption needed to make „pushfoward of gradings along maps of indexing sets“ – see draft PR #39356 – work in some `SetLike` generality.
Given `{S M : Type*} [SetLike S M] [Monoid M] [SubmonoidClass S M]`, we have canonical maps
```
S → Submonoid M → Set M
```
The first is `Submonoid.ofClass`, the second and the composition are `coe` maps coming from the `SetLike` structures. Depending on `S`, these maps may or may not satisfy various properties with respect the lattice structures on `Submonoid M` and `Set M`. Mathlib so far includes the type class `[IsConcreteLE S M]`, which asserts that the composition `S → Set M` is order-preserving and order-reflecting. The type class defined here asserts that the first map, `S → Submonoid M`, preserves suprema.
In examples such as `S = Subgroup M`, `S = Submodule R M`, much more is true – in these cases, `S` is a complete sublattice of `Submonoid M`. But there are also examples where only the weaker property defined here holds, e.g. `S = OpenSubgroup M` for a topological group `M`.
Note on `outParam`: I did *not* write `(M : outParam Type*)` in the assumptions of `SubmonoidClass.IsConcreteSSup` in accordance with the [DocString of `Setlike`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Data/SetLike/Basic.html#SetLike). However, we do have `(B : outParam Type*)` in the definition of `IsConcreteLE`, so perhaps I'm misinterpreting the DocString.
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-algebra
label:t-algebra$ |
56/0 |
Mathlib.lean,Mathlib/Algebra/Group/Submonoid/SSup.lean |
2 |
2 |
['github-actions'] |
nobody |
7-57334 7 days ago |
7-57403 7 days ago |
7-57772 7 days |
| 39646 |
YaelDillies author:YaelDillies |
feat(Algebra/Order): maximally varying version of `prod_le_prod_of_subset_of_one_le` |
We need this for `gcongr`.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
49/26 |
Mathlib/Algebra/Module/ZLattice/Summable.lean,Mathlib/Algebra/Order/BigOperators/Group/Finset.lean,Mathlib/Algebra/Order/BigOperators/GroupWithZero/Finset.lean,Mathlib/Analysis/Complex/Exponential.lean |
4 |
7 |
['YaelDillies', 'b-mehta', 'github-actions'] |
nobody |
7-55644 7 days ago |
8-56412 8 days ago |
8-59637 8 days |
| 36275 |
smmercuri author:smmercuri |
feat: norm for the finite adele ring of a number field |
---
- [x] depends on: #35820
[](https://gitpod.io/from-referrer/)
|
|
137/1 |
Mathlib.lean,Mathlib/NumberTheory/NumberField/Completion/FinitePlace.lean,Mathlib/NumberTheory/NumberField/FiniteAdeleRing.lean,Mathlib/Topology/Algebra/Valued/NormedValued.lean |
4 |
4 |
['github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
nobody |
7-53630 7 days ago |
7-53703 7 days ago |
7-54732 7 days |
| 39621 |
chrisflav author:chrisflav |
refactor(Topology): use `WithTopology` to define `WithConstructibleTopology` |
We replace the type synonym `WithConstructibleTopology` by `WithTopology _ (constructibleTopology X)`. This breaks the def-eq `X = WithConstructibleTopology X`, which was luckily not abused much yet.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
38/5 |
Mathlib/Topology/Compactness/Compact.lean,Mathlib/Topology/Spectral/ConstructibleTopology.lean,Mathlib/Topology/WithTopology.lean |
3 |
2 |
['github-actions', 'plp127'] |
nobody |
7-31183 7 days ago |
9-33374 9 days ago |
9-33143 9 days |
| 38234 |
vihdzp author:vihdzp |
chore: make `IsSuccLimit` a structure |
This lets us name the fields. Note that the `mk_iff` lemma overwrites a recently deprecated theorem.
---
[](https://gitpod.io/from-referrer/)
|
t-order
maintainer-merge
|
40/33 |
Mathlib/Order/SuccPred/InitialSeg.lean,Mathlib/Order/SuccPred/Limit.lean |
2 |
6 |
['YaelDillies', 'github-actions', 'plp127'] |
nobody |
7-19636 7 days ago |
20-64095 20 days ago |
36-52151 36 days |
| 37718 |
SabrinaJewson author:SabrinaJewson |
feat(Order): add conversions from `Std` order typeclasses to Mathlib ones |
`{Preorder, PartialOrder, LinearOrder}.ofStd` exist to facilitate convenient translation from `Std` order typeclasses to Mathlib ones.
The design is modelled closely after [`Init.Data.Order.PackageFactories`](https://leanprover-community.github.io/mathlib4_docs/Init/Data/Order/PackageFactories.html) (`Std.PreorderPackage` is equivalent-ish to Mathlib’s `Preorder`, and same for partial and linear orders). The `OfStdArgs` types allow conveniently bundling a whole bunch of default arguments together in a way that allows one default argument set to `extends` another.
---
[](https://gitpod.io/from-referrer/)
|
t-order
new-contributor
maintainer-merge
|
391/0 |
Mathlib.lean,Mathlib/Order/Std.lean,MathlibTest/OrderOfStd.lean |
3 |
9 |
['SabrinaJewson', 'YaelDillies', 'github-actions'] |
YaelDillies assignee:YaelDillies |
7-17651 7 days ago |
8-9447 8 days ago |
53-3558 53 days |
| 39697 |
sorrachai author:sorrachai |
feat(Data/Tree/Basic): add Membership instance, new notation, rename Tree |
Summary:
1. [Rename]([#CSLib > Splay tree PR: BinaryTree vs Tree @ 💬](https://leanprover.zulipchat.com/#narrow/channel/513188-CSLib/topic/Splay.20tree.20PR.3A.20BinaryTree.20vs.20Tree/near/596482765)) from Tree to BinaryTree, which propagates the changes to other files that use it.
2. Add membership instance, prove decidability of membership.
3. Add toListInOrder, toListPreOrder, toListPostOrder
Suggestion based on the discussion in the cslib [thread](https://leanprover.zulipchat.com/#narrow/channel/513188-CSLib/topic/Splay.20tree.20PR/near/596568391)[#CSLib > Splay tree PR @ 💬](https://leanprover.zulipchat.com/#narrow/channel/513188-CSLib/topic/Splay.20tree.20PR/near/596568391).
---
* depends on: #39707 |
new-contributor |
187/75 |
Mathlib/Combinatorics/Enumerative/Catalan/Tree.lean,Mathlib/Combinatorics/Enumerative/DyckWord.lean,Mathlib/Data/Tree/Basic.lean,Mathlib/Data/Tree/Get.lean,Mathlib/Data/Tree/Traversable.lean,Mathlib/Tactic/CancelDenoms/Core.lean,docs/overview.yaml |
7 |
4 |
['eric-wieser', 'github-actions', 'sorrachai'] |
nobody |
7-10666 7 days ago |
7-42226 7 days ago |
7-44050 7 days |
| 35069 |
A-M-Berns author:A-M-Berns |
feat(Geometry/Polygon): simple polygons and boundary map |
This PR introduces Simple polygons with the predicate `IsSimple`, which captures the idea of a non-self-intersecting boundary, in the file Simple.lean. In the file Boundary.lean, a boundary map from `AddCircle n` is defined. I prove that the range of this map is the boundary and that this map is injective if and only if the polygon is simple. I kept Boundary.lean and Simple.lean separate because future results will include stuff just about the boundary map independent of simplicity (e.g. that it is continuous in the appropriate setting) and stuff just about simple polygons independent of the boundary map (e.g. that for n = 3, IsSimple iff HasNondegenerateVertices.) I used Claude Code to help generate some of the proof material, but I golfed and edited all AI contribution.
- [x] depends on: #34598
---
|
new-contributor
t-euclidean-geometry
LLM-generated
|
360/0 |
Mathlib.lean,Mathlib/Geometry/Polygon/Boundary.lean,Mathlib/Geometry/Polygon/Simple.lean,Mathlib/Logic/Equiv/Fin/Rotate.lean |
4 |
30 |
['A-M-Berns', 'eric-wieser', 'github-actions', 'joneugster', 'jsm28', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'vihdzp', 'wwylele'] |
nobody |
7-2543 7 days ago |
93-28398 93 days ago |
95-62453 95 days |
| 35402 |
samueloettl author:samueloettl |
feat(Dynamics/BirkhoffSum): birkhoffAverage const |
---
I think this is useful and one of these should be a simp lemma.
I'm not really sure if I got the naming of the theorems correct.
When generalizing to the assumption (n : R) ≠ 0 instead of the special case CharZero R with n ≠ 0 I had to use "open Classical in". I'm a bit unfamiliar with that part so please check if this makes sense. See also https://github.com/leanprover-community/mathlib4/pull/35307#discussion_r2823586252
[](https://gitpod.io/from-referrer/)
|
t-dynamics
new-contributor
|
14/0 |
Mathlib/Dynamics/BirkhoffSum/Average.lean |
1 |
26 |
['Maldooor', 'github-actions', 'lua-vr', 'mcdoll', 'samueloettl'] |
sgouezel assignee:sgouezel |
7-1369 7 days ago |
30-41892 30 days ago |
96-40474 96 days |
| 39033 |
tb65536 author:tb65536 |
feat(Analysis/DirichletEigenvalue): Dirichlet eigenvalues of a set |
This PR defines the Dirichlet eigenvalues of a set (in the sense of "can you hear the shape of a drum").
---
[](https://gitpod.io/from-referrer/)
|
t-analysis |
58/0 |
Mathlib.lean,Mathlib/Analysis/DirichletEigenvalue.lean |
2 |
1 |
['github-actions'] |
sgouezel assignee:sgouezel |
7-1361 7 days ago |
22-44867 22 days ago |
22-44638 22 days |
| 39738 |
NoahW314 author:NoahW314 |
feat(Algebra/Algebra/Bilinear): generalize to `NonUnitalNonAssocCommSemiring` |
Complete a TODO which can now be done since #28604 is merged.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
2/4 |
Mathlib/Algebra/Algebra/Bilinear.lean |
1 |
1 |
['github-actions'] |
nobody |
6-80103 6 days ago |
6-80178 6 days ago |
6-79947 6 days |
| 39518 |
abeldonate author:abeldonate |
feat(RingTheory/LocalProperties/Projective): Projective Module theorem |
Theorem: R Noetherian, M finitely generated R-Mod. Then:
M projective iff M_m free for all m maximal
|
t-ring-theory
new-contributor
large-import
|
21/0 |
Mathlib/RingTheory/LocalProperties/Projective.lean |
1 |
9 |
['abeldonate', 'github-actions', 'mbkybky', 'vlad902'] |
nobody |
6-63458 6 days ago |
10-41077 10 days ago |
10-83101 10 days |
| 39530 |
RaggedR author:RaggedR |
feat(Combinatorics/SimpleGraph): group actions on simple graphs |
This adds the first connection between Mathlib's MulAction and SimpleGraph libraries. The GraphAction class asserts that a group action on the vertex type preserves the adjacency relation, and builds on it to define vertex-transitivity and arc-transitivity for graphs.
The GraphAction typeclass gives adj_smul_iff (the biconditional for group actions) and toIso (each group element induces a graph automorphism). The IsVertexTransitive class combines GraphAction with IsPretransitive, and IsArcTransitive requires transitivity on ordered adjacent pairs (arcs).
The main theorem is the standard characterization: a graph is arc-transitive if and only if it is vertex-transitive and locally transitive (the stabilizer of each vertex acts transitively on its neighbors). The forward direction is proved directly by composing a vertex-transporting element with a neighbor-transporting stabilizer element. The reverse direction shows that an arc-transitive graph with no isolated vertices is vertex-transitive.
These definitions are the algebraic graph theory prerequisites for formalizing coset graphs (Sabidussi's construction) and the characterization of symmetric graphs via double cosets and involutions (Lorimer's theorem).
---
LLM tools were used to assist with Lean formalization. The mathematical content is the author's own work. |
t-combinatorics
new-contributor
LLM-generated
|
130/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Action.lean |
2 |
7 |
['RaggedR', 'b-mehta', 'github-actions', 'mathlib-bors'] |
nobody |
6-52826 6 days ago |
6-52826 6 days ago |
11-21045 11 days |
| 38194 |
ryanncode author:ryanncode |
feat(LinearAlgebra/BilinearForm): add indefinite metrics |
Add the `IndefiniteMetric` structure to support vector spaces equipped with a non-degenerate, symmetric, indefinite bilinear form.
Provide the algebraic foundation for indefinite inner product spaces by formalizing the metric via `LinearMap.BilinForm` and extracting its associated quadratic form without enforcing the `IsPosSemidef` typeclass.
Previously, mathlib required strictly positive-definite metrics to instantiate inner product spaces (`InnerProductSpace`), which prevented the formalization of indefinite geometries without causing typeclass inference failures. Bridge this gap by isolating the symmetric bilinear form from topological and positivity constraints, allowing the library to handle generalized indefinite metric spaces safely.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
47/0 |
Mathlib.lean,Mathlib/LinearAlgebra/BilinearForm/IndefiniteMetric.lean |
2 |
5 |
['dagurtomas', 'github-actions', 'mathlib-merge-conflicts', 'ryanncode'] |
nobody |
6-45026 6 days ago |
6-46771 6 days ago |
22-16309 22 days |
| 39412 |
mbkybky author:mbkybky |
feat(RingTheory/Flat): a finite flat `R`-module `M` is locally free if `rankAtStalk M` is constant |
Let `M` be a finite flat `R`-module, `p` be a prime ideal of `R`. We show that if `rankAtStalk M` is constant, then there exists `a ∉ p` such that the `M` is free after localization away from `a`.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
136/2 |
Mathlib.lean,Mathlib/Algebra/Module/FinitePresentation.lean,Mathlib/Algebra/Module/LocalizedModule/Submodule.lean,Mathlib/LinearAlgebra/FiniteDimensional/Basic.lean,Mathlib/RingTheory/Flat/LocallyFree.lean,Mathlib/RingTheory/Localization/BaseChange.lean,Mathlib/RingTheory/Spectrum/Prime/FreeLocus.lean,Mathlib/RingTheory/Support.lean |
8 |
4 |
['github-actions', 'robin-carlier'] |
nobody |
6-42799 6 days ago |
11-33191 11 days ago |
14-37944 14 days |
| 38698 |
Thmoas-Guan author:Thmoas-Guan |
feat(RingTheory/Regular): freeness of `QuotSMulTop` |
For finitely generated module `M` over Noetherian local ring `(R, m)`, if `x ∈ m` is `M`-regular, `M/xM` is free over `R/(x)` iff `M` is free over `R`.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
95/0 |
Mathlib.lean,Mathlib/RingTheory/Nakayama.lean,Mathlib/RingTheory/Regular/Free.lean |
3 |
12 |
['Thmoas-Guan', 'chrisflav', 'github-actions'] |
chrisflav assignee:chrisflav |
6-37703 6 days ago |
8-68159 8 days ago |
30-44043 30 days |
| 39212 |
emlis42 author:emlis42 |
feat(Algebra/ContinuedFractions): add `partNums!` and `partDens!` |
This PR adds `partNums!` and `partDens!`, which provide infinite stream representations for the sequences of partial numerators and denominators of a generalized continued fraction. |
t-algebra
new-contributor
label:t-algebra$ |
8/0 |
Mathlib/Algebra/ContinuedFractions/Basic.lean |
1 |
4 |
['emlis42', 'github-actions', 'grunweg'] |
nobody |
6-29566 6 days ago |
18-31326 18 days ago |
18-31095 18 days |
| 38970 |
themathqueen author:themathqueen |
chore(Analysis/InnerProductSpace/Projection): rename `orthogonalProjection` to `orthogonalProjectionOnto` |
To match the current (continuous) linear projection to a submodule along its complement `Submodule.projection(Onto)(L)`, we change `Submodule.orthogonalProjection` to `Submodule.orthogonalProjectionOnto` (and later will change `Submodule.starProjection` to `Submodule.orthogonalProjection`).
---
Zulip thread: [#**mathlib4>Two variants of linear projections**](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Two.20variants.20of.20linear.20projections/with/591234152)
[](https://gitpod.io/from-referrer/)
|
t-analysis |
267/183 |
Mathlib/Analysis/InnerProductSpace/Adjoint.lean,Mathlib/Analysis/InnerProductSpace/GramSchmidtOrtho.lean,Mathlib/Analysis/InnerProductSpace/MeanErgodic.lean,Mathlib/Analysis/InnerProductSpace/PiL2.lean,Mathlib/Analysis/InnerProductSpace/Positive.lean,Mathlib/Analysis/InnerProductSpace/ProdL2.lean,Mathlib/Analysis/InnerProductSpace/Projection/Basic.lean,Mathlib/Analysis/InnerProductSpace/Projection/FiniteDimensional.lean,Mathlib/Analysis/InnerProductSpace/Projection/Reflection.lean,Mathlib/Analysis/InnerProductSpace/Projection/Submodule.lean,Mathlib/Analysis/InnerProductSpace/Spectrum.lean,Mathlib/Analysis/InnerProductSpace/l2Space.lean,Mathlib/Geometry/Euclidean/Projection.lean,Mathlib/Geometry/Euclidean/Volume/Measure.lean,Mathlib/Geometry/Manifold/Instances/Sphere.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/CondexpL2.lean,Mathlib/MeasureTheory/Measure/Hausdorff.lean,Mathlib/Topology/MetricSpace/HausdorffDimension.lean,docs/overview.yaml,docs/undergrad.yaml |
20 |
17 |
['ADedecker', 'eric-wieser', 'github-actions', 'mathlib-merge-conflicts', 'themathqueen'] |
mcdoll assignee:mcdoll |
6-28290 6 days ago |
6-28326 6 days ago |
23-75654 23 days |
| 39696 |
jsm28 author:jsm28 |
refactor(LinearAlgebra/Orientation,LinearAlgebra/AffineSpace/FiniteDimensional): instances for arbitrary orientations |
Based on suggestions by @kim-em on Zulip https://leanprover.zulipchat.com/#narrow/channel/144837-PR-reviews/topic/PRs.20towards.20IMO.20geometry.202024.20P4/near/596946072 add convenience scoped instances for choosing an arbitrary orientation of a module, and for the `finrank` of the span of the vertices of a simplex.
Note: I don't understand why the latter scoped instance is only found automatically in one of the two places using it; in `Sphere/Power.lean` it's necessary to use `Affine.Simplex.fact_finrank_direction_affineSpan_eq` rather than relying on typeclass inference, but in `Angle/Sphere.lean` typeclass inference suffices.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-euclidean-geometry
label:t-algebra$ |
26/23 |
Archive/Imo/Imo2019Q2.lean,Mathlib/Geometry/Euclidean/Angle/Sphere.lean,Mathlib/Geometry/Euclidean/Sphere/Power.lean,Mathlib/LinearAlgebra/AffineSpace/FiniteDimensional.lean,Mathlib/LinearAlgebra/Orientation.lean |
5 |
2 |
['github-actions', 'mathlib-merge-conflicts'] |
nobody |
6-23218 6 days ago |
6-23251 6 days ago |
7-42377 7 days |
| 39576 |
plp127 author:plp127 |
chore(Topology): generalize `Topology.IsEmbedding.perfectlyNormalSpace` |
Generalize theorem `Topology.IsEmbedding.perfectlyNormalSpace` to inducing maps. Generalize some other theorem along the way. Rename `isGδ_induced` to `IsGδ.preimage`, to match `IsOpen.preimage` and `IsClosed.preimage`.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
29/27 |
Mathlib/Topology/Baire/LocallyCompactRegular.lean,Mathlib/Topology/GDelta/Basic.lean,Mathlib/Topology/Separation/GDelta.lean,Mathlib/Topology/Separation/PerfectlyNormal.lean,Mathlib/Topology/Separation/Regular.lean |
5 |
2 |
['github-actions', 'mathlib-merge-conflicts'] |
nobody |
6-20493 6 days ago |
6-20528 6 days ago |
10-38668 10 days |
| 37716 |
slavanaprienko author:slavanaprienko |
feat(LinearAlgebra/Matrix/Determinant): Desnanot-Jacobi identity |
This PR adds the Desnanot-Jacobi identity (also known as the Lewis Carroll identity or Dodgson condensation): for any (n+2)×(n+2) matrix M over a commutative ring,
$$\det(M) \cdot \det(M_{1,n}^{1,n}) = \det(M_1^1) \cdot \det(M_n^n) - \det(M_1^n) \cdot \det(M_n^1)$$
The proof follows Bressoud's *Proofs and Confirmations* (Cambridge University Press, 1999): multiply M by an auxiliary matrix built from columns of the adjugate, then compare determinants. This yields the identity premultiplied by det(M). To cancel, we pass to a universal polynomial ring (an integral domain with nonzero determinant), then specialize back to arbitrary commutative rings.
It seems there's some interest in adding this:
https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Determinantal.20identity.20and.20the.20Cauchy.20matrix.20determinant/with/582946873
--- |
t-algebra
new-contributor
label:t-algebra$ |
217/0 |
Mathlib.lean,Mathlib/LinearAlgebra/Matrix/Determinant/DesnanotJacobi.lean |
2 |
13 |
['SnirBroshi', 'github-actions', 'grunweg', 'kim-em', 'slavanaprienko'] |
nobody |
6-10075 6 days ago |
18-20032 18 days ago |
19-58031 19 days |
| 39372 |
yuanyi-350 author:yuanyi-350 |
refactor(NumberTheory): golf `Mathlib/NumberTheory/ModularForms/EisensteinSeries/MDifferentiable` |
- rewrites `eisensteinSeriesSIF_mdifferentiable` to use `UpperHalfPlane.mdifferentiable_iff` directly and conclude from local uniform convergence of the Eisenstein series
Extracted from #38144
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
|
1/6 |
Mathlib/NumberTheory/ModularForms/EisensteinSeries/MDifferentiable.lean |
1 |
4 |
['github-actions', 'mathlib-merge-conflicts', 'yuanyi-350'] |
nobody |
6-3899 6 days ago |
6-3937 6 days ago |
15-11911 15 days |
| 35753 |
Vilin97 author:Vilin97 |
feat(Topology/Algebra/Order): regular grid helpers and piecewise linear interpolation |
Make API for piecewise linear interpolation on regular grids. I need these to for ODE time-stepping methods, like forward Euler, and later Runge–Kutta methods.
Follow-up PR: #35755 (forward Euler method convergence).
I don't know if these numerical analysis ODE-solving methods even belong in mathlib. If someone could advise me on it, I would appreciate it.
---
The initial proof was produced by [Aristotle](https://aristotle.harmonic.fun). The code was iteratively refined (factoring out lemmas, golfing, simplifying proofs) using Claude Code.
- [ ] depends on: #38091 |
t-topology
new-contributor
LLM-generated
maintainer-merge
|
201/0 |
Mathlib.lean,Mathlib/Topology/Algebra/Order/PiecewiseLinear.lean |
2 |
59 |
['Vilin97', 'YanYablonovskiy', 'adomani', 'botbaki-review', 'copilot-pull-request-reviewer', 'dagurtomas', 'eric-wieser', 'github-actions', 'grunweg', 'j-loreaux', 'mathlib-dependent-issues', 'wwylele'] |
ADedecker assignee:ADedecker |
6-1036 6 days ago |
28-13263 28 days ago |
60-62112 60 days |
| 39763 |
NoahW314 author:NoahW314 |
feat(Algebra/GroupWithZero/Divisibility): add `mul_dvd_left_iff_isUnit` |
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
9/0 |
Mathlib/Algebra/GroupWithZero/Divisibility.lean |
1 |
1 |
['github-actions'] |
nobody |
5-78642 5 days ago |
5-78722 5 days ago |
5-78491 5 days |
| 39075 |
Thmoas-Guan author:Thmoas-Guan |
feat(Algebra/CommRingCat): colimit of local ring via local hom |
In this PR, we deal with filtered colimit of local ring via local homomorphisms, proving it is
again local, with maximal ideal equal to the union of images of maximal ideals.
Co-authored-by: Wang Jingting
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
209/0 |
Mathlib.lean,Mathlib/Algebra/Category/Ring/FilteredColimitsLocal.lean |
2 |
1 |
['github-actions'] |
nobody |
5-64581 5 days ago |
5-64648 5 days ago |
21-47317 21 days |
| 39765 |
vlad902 author:vlad902 |
doc(RingTheory): fix local ring doc comment |
The predicate for local rings was updated to the current definition on non-commutative semirings back in mathlib3, but the outdated comment stating that local rings are commutative rings with a unique maximal ideal has not been updated since.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
4/4 |
Mathlib/RingTheory/LocalRing/Defs.lean |
1 |
1 |
['github-actions'] |
nobody |
5-61833 5 days ago |
5-61915 5 days ago |
5-61684 5 days |
| 37642 |
SnirBroshi author:SnirBroshi |
chore(Combinatorics/SimpleGraph): tidy various files |
---
Concept inspired by @Ruben-VandeVelde :)
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
maintainer-merge
|
73/62 |
Mathlib/Combinatorics/SimpleGraph/Coloring/VertexColoring.lean,Mathlib/Combinatorics/SimpleGraph/Copy.lean,Mathlib/Combinatorics/SimpleGraph/Extremal/Basic.lean,Mathlib/Combinatorics/SimpleGraph/IncMatrix.lean,Mathlib/Combinatorics/SimpleGraph/Maps.lean,Mathlib/Combinatorics/SimpleGraph/Trails.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Decomp.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Operations.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Subwalks.lean |
9 |
9 |
['SnirBroshi', 'YaelDillies', 'github-actions', 'mathlib-merge-conflicts'] |
nobody |
5-44351 5 days ago |
5-44386 5 days ago |
53-44814 53 days |
| 39773 |
kbuzzard author:kbuzzard |
perf: add some fast_instance% |
This PR adds some `fast_instance%`s, which tidies up some terms.
See [#mathlib4 > fast_instance% plans](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/fast_instance.25.20plans/with/597402311) for explicit descriptions of what every change in this PR actually does to the terms in question.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
6/4 |
Mathlib/Algebra/Group/Pi/Basic.lean,Mathlib/Algebra/Group/TypeTags/Basic.lean |
2 |
3 |
['github-actions', 'kbuzzard', 'leanprover-radar'] |
nobody |
5-42066 5 days ago |
5-43606 5 days ago |
5-43375 5 days |
| 39783 |
SnirBroshi author:SnirBroshi |
feat(Order/Interval/Finset): `Set.ncard` lemmas for `LocallyFiniteOrder` |
Followup to #39414 which untagged `Fintype.card_I??` as `@[simp]`.
Adds `Cardinal.mk`/`Set.encard`/`Set.ncard` lemmas for the 8 interval sets `Set.I??` (= 24 lemmas),
that convert them to `Finset.card` over the corresponding `Finset.I??` from a `LocallyFiniteOrder` instance.
---
`simp`? I think it's a bit strange since the `LocallyFiniteOrder` instance could have crazy definitions for the finset intervals which aren't "simpler", though the instances we currently have are simple.
[](https://gitpod.io/from-referrer/)
|
t-order |
115/0 |
Mathlib.lean,Mathlib/Order/Interval/Finset/Card.lean |
2 |
1 |
['github-actions'] |
nobody |
5-33372 5 days ago |
5-33440 5 days ago |
5-33508 5 days |
| 36501 |
AntoineChambert-Loir author:AntoineChambert-Loir |
feat(RingTheory/GradedAlgebra/Homogeneous/RingQuot): graded structure on the quotient of a graded ring by a homogeneous ideal |
Define the graded structure on the quotient of a graded ring by a homogeneous ideal
Co-authored with: @mariainesdff
(Possible TODO:
- Maybe define the graded structure on the quotient of a graded module by a homogeneous submodule.
- There is also an issue of working with ring congruences rather than with ideals. )
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
504/20 |
Mathlib.lean,Mathlib/Algebra/DirectSum/Decomposition.lean,Mathlib/AlgebraicGeometry/ProjectiveSpectrum/Basic.lean,Mathlib/AlgebraicGeometry/ProjectiveSpectrum/Scheme.lean,Mathlib/Data/DFinsupp/BigOperators.lean,Mathlib/RingTheory/GradedAlgebra/Basic.lean,Mathlib/RingTheory/GradedAlgebra/Homogeneous/Ideal.lean,Mathlib/RingTheory/GradedAlgebra/Homogeneous/RingQuot.lean,Mathlib/RingTheory/GradedAlgebra/HomogeneousLocalization.lean,Mathlib/RingTheory/Ideal/Span.lean |
10 |
133 |
['AntoineChambert-Loir', 'chrisflav', 'eric-wieser', 'github-actions', 'mathlib-merge-conflicts', 'robin-carlier'] |
eric-wieser and robin-carlier assignee:eric-wieser assignee:robin-carlier |
5-30005 5 days ago |
5-30082 5 days ago |
53-20866 53 days |
| 39545 |
Hagb author:Hagb |
feat(Order/OrderIsoNat): some lemmas about `((· < ·) : ℕ → ℕ → Prop) ↪r r` |
This PR contains several lemmas about relation embedding from `<` in `Nat`, well order, and (in)finiteness.
- `RelEmbedding.infinite_iff_nonempty_relEmbedding_of_isWellOrder`: a type with a well order relation is infinite iff there is such a relation embedding.
- `RelEmbedding.finite_iff_empty_relEmbedding_of_isWellOrder`: a finite variant of `infinite_iff_nonempty_relEmbedding_of_isWellOrder`
- `IsWellOrder.finite_of_isWellOrder_of_isWellOrder_swap`: a type with a linear order relation well founded on both directions is finite.
- `instFiniteOfWellFoundedLTOfWellFoundedGT`: an instance variant of `IsWellOrder.finite_of_isWellOrder_of_isWellOrder_swap` on `WellFounded{LT,GT}`.
- `RelEmbedding.infinite_iff_nonempty_relEmbedding_lt_or_nonempty_relEmbedding_gt`: a type with a linear order relation is infinite iff there are both relation embedding between `<` in `Nat` and this relation, and between `>` in `Nat` and this relation.
- `RelEmbedding.finite_iff_isEmpty_relEmbedding_lt_and_isEmpty_relEmbedding_gt`: a finite variant of `infinite_iff_nonempty_relEmbedding_lt_or_nonempty_relEmbedding_gt`.
---
[](https://gitpod.io/from-referrer/)
Edit: remove the description on the original motivation since `WellQuasiOrdered` instead of theorems in this PR can be used for that goal.
`RelEmbedding.finite_iff_empty_relEmbedding_of_isWellOrder` might be used for proof of
```lean
example {α β γ} [LinearOrder α] [LinearOrder β] [WellFoundedLT α] [WellFoundedLT β] [LinearOrder γ]
{f : α × β ≃ γ} (mono : Monotone f) : WellFoundedLT γ := sorry
```
The latter will be used for
```lean
example {α β γ} [Finite α] [LinearOrder β] [WellFoundedLT β] [LinearOrder γ]
{f : (α → β) ≃ γ} (mono : Monotone f) : WellFoundedLT γ := sorry
```
And the finial goal is the well-foundedness of monomial order when the index type `σ` is finite (under the definition in #39214). |
t-order |
58/0 |
Mathlib/Order/OrderIsoNat.lean |
1 |
15 |
['Hagb', 'SnirBroshi', 'github-actions', 'leanprover-radar', 'vihdzp'] |
nobody |
5-28287 5 days ago |
10-28320 10 days ago |
10-63529 10 days |
| 37752 |
JovanGerb author:JovanGerb |
chore(Order/CompleteLattice/Lemmas): use `to_dual` |
Use `to_dual` for lemmas about `CompleteLattice`.
---
[](https://gitpod.io/from-referrer/)
|
t-order
maintainer-merge
|
33/56 |
Mathlib/Order/CompleteLattice/Lemmas.lean,Mathlib/Tactic/Translate/ToDual.lean |
2 |
6 |
['JovanGerb', 'YaelDillies', 'github-actions', 'vihdzp'] |
nobody |
5-28080 5 days ago |
5-28147 5 days ago |
52-24533 52 days |
| 28685 |
mitchell-horner author:mitchell-horner |
feat(Combinatorics/SimpleGraph): prove the minimal-degree version of the Erdős-Stone theorem |
Proves the minimal degree-version of the Erdős-Stone theorem:
If `G` has a minimal degree of at least `(1 - 1 / r + o(1)) * card V`, then `G` contains a copy of a `completeEquipartiteGraph` in `r + 1` parts each of size `t`.
The double-counting construction from the proof is available in `namespace ErdosStone`.
---
- [x] depends on: #25843
- [x] depends on: #27597
- [x] depends on: #27599
- [x] depends on: #28443
- [x] depends on: #28445
- [x] depends on: #28446
- [x] depends on: #28447
This is the first of several pull requests towards the full Erdős-Stone(-Simonovits) theorem, hence the name of the file.
[](https://gitpod.io/from-referrer/) |
t-combinatorics
maintainer-merge
|
329/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Extremal/ErdosStoneSimonovits.lean |
2 |
19 |
['YaelDillies', 'b-mehta', 'github-actions', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot', 'mitchell-horner', 'robin-carlier'] |
nobody |
5-2544 5 days ago |
26-2681 26 days ago |
86-11192 86 days |
| 39436 |
dtumad author:dtumad |
chore: Add `seqLeft` and `seqRight` unfolding to monad_norm simp set |
This PR adds `seqLeft_eq_bind` and `seqRight_eq_bind` to `monad_norm`, so that `<*` and `*>` get unfolded in the same way as `<*>` already does when using the `simp` set.
---
[](https://gitpod.io/from-referrer/)
|
t-meta
new-contributor
|
1/1 |
Mathlib/Tactic/Attr/Core.lean |
1 |
2 |
['github-actions'] |
dwrensha assignee:dwrensha |
5-2085 5 days ago |
14-15288 14 days ago |
14-15057 14 days |
| 30109 |
scholzhannah author:scholzhannah |
feat: the subcomplexes of a (relative classical) CW complex form a completely distributive lattice |
In this PR we prove that the space of subcomplexes `Subcomplex C` of a (relative classical) CW complex `C` is a `CompletelyDistribLattice`.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
304/1 |
Mathlib/Topology/CWComplex/Classical/Subcomplex.lean |
1 |
26 |
['ADedecker', 'github-actions', 'j-loreaux', 'scholzhannah'] |
alreadydone assignee:alreadydone |
5-931 5 days ago |
35-47309 35 days ago |
42-29770 42 days |
| 33640 |
JovanGerb author:JovanGerb |
feat: tool for finding duplicate declarations |
This PR defines a tool for finding duplicate declarations automatically. This can be used to help fix this technical debt.
---
[](https://gitpod.io/from-referrer/)
|
t-meta |
201/0 |
Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/DuplicateDecls.lean,MathlibTest/Tactic/DuplicateDecls.lean,MathlibTest/Tactic/DuplicateDeclsAux.lean |
5 |
1 |
['github-actions'] |
dwrensha assignee:dwrensha |
5-930 5 days ago |
5-48380 5 days ago |
5-48232 5 days |
| 35610 |
IvanRenison author:IvanRenison |
feat(Data/Fin): add several lemmas about subtraction of `Fin.{castLT, castAdd, castSucc, castPred}` |
---
[](https://gitpod.io/from-referrer/)
|
t-data |
66/0 |
Mathlib/Data/Fin/Basic.lean,Mathlib/Data/Fin/SuccPred.lean |
2 |
13 |
['IvanRenison', 'chrisflav', 'github-actions', 'robin-carlier', 'wwylele'] |
Vierkantor assignee:Vierkantor |
5-929 5 days ago |
28-12574 28 days ago |
93-45851 93 days |
| 38142 |
SnirBroshi author:SnirBroshi |
feat(Order/SuccPred/CompleteLinearOrder): generalize `csSup_mem_of_not_isSuccLimit` |
Given `s.Nonempty` and `BddAbove s` we can conclude `sSup s ∈ s` using either:
- `csSup_mem_of_not_isSuccPrelimit`, given `ConditionallyCompleteLinearOrder` and `¬IsSuccPrelimit (sSup s)`
- `csSup_mem_of_not_isSuccLimit`, given `ConditionallyCompleteLinearOrderBot` and `¬IsSuccLimit (sSup s)`
We generalize both to a theorem that requires `ConditionallyCompleteLinearOrder` and `¬IsSuccLimit (sSup s)`.
This creates 8 theorems that require `¬IsSuccPrelimit` but are now easily proved with the `¬IsSuccLimit` theorems, we replace `csSup_mem_of_not_isSuccPrelimit`/`exists_eq_ciSup_of_not_isSuccPrelimit` with their primed `ConditionallyCompleteLinearOrderBot` theorems, and deprecates the other 6.
Tags a random `to_dual` (in `ConditionallyCompleteLattice/Basic.lean`) to let us `to_dual`ize the new lemmas.
---
~~Should we also deprecate the 8 theorems that require `¬IsSuccPrelimit` and now use `mt`?~~
[](https://gitpod.io/from-referrer/)
|
t-order |
55/42 |
Mathlib/Order/ConditionallyCompleteLattice/Basic.lean,Mathlib/Order/SuccPred/CompleteLinearOrder.lean,Mathlib/SetTheory/Cardinal/Order.lean |
3 |
9 |
['SnirBroshi', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp'] |
bryangingechen assignee:bryangingechen |
5-925 5 days ago |
27-82551 27 days ago |
42-80726 42 days |
| 38214 |
emlis42 author:emlis42 |
feat(Algebra/ContinuedFractions): add Euler's continued fraction |
This PR formalizes Euler’s continued fractions by providing `Euler` which construct one by giving head term and coefficients with some basic property.
We also introduce a transformation `GenContFract.toEuler` that maps a generalized continued fraction `g : GenContFract K` to an equivalent Euler-form continued fraction. |
new-contributor
t-algebra
label:t-algebra$ |
262/0 |
Mathlib.lean,Mathlib/Algebra/ContinuedFractions/Euler.lean |
2 |
15 |
['github-actions', 'mathlib-bors', 'wwylele'] |
alreadydone assignee:alreadydone |
5-924 5 days ago |
36-29059 36 days ago |
36-32580 36 days |
| 39256 |
Sfgangloff author:Sfgangloff |
feat(SymbolicDynamics): add monotonicity lemma for LanguageOn |
In Symbolic dynamics.
Proof that the language of a set of configurations is monotone with respect to inclusion of configuration sets:
X ⊆ Y → LanguageOn X U ⊆ LanguageOn Y U
The proof is a direct unfolding of definitions: a pattern in the language of X comes from restricting some configuration x ∈ X, and inclusion X ⊆ Y allows the same witness to be used for Y.
Related to issue #39252 |
t-dynamics
new-contributor
|
9/1 |
Mathlib/Dynamics/SymbolicDynamics/Basic.lean |
1 |
3 |
['github-actions'] |
ADedecker assignee:ADedecker |
5-923 5 days ago |
17-40173 17 days ago |
17-39942 17 days |
| 39799 |
NoahW314 author:NoahW314 |
chore(RingTheory/Ideal/Operations): deprecate duplicate theorem `Ideal.span_mul_span'` |
`Ideal.span_mul_span'` is identical to `Ideal.span_mul_span`.
---
[](https://gitpod.io/from-referrer/)
At one point, `Ideal.span_mul_span` and `Ideal.span_mul_span'` were distinct, but `Ideal.span_mul_span` was changed in #22151 to be identical to `Ideal.span_mul_span'`. |
t-ring-theory |
6/7 |
Mathlib/RingTheory/GradedAlgebra/Homogeneous/Ideal.lean,Mathlib/RingTheory/Ideal/Norm/RelNorm.lean,Mathlib/RingTheory/Ideal/Operations.lean,scripts/nolints_prime_decls.txt |
4 |
1 |
['github-actions'] |
nobody |
5-46 5 days ago |
5-315 5 days ago |
5-84 5 days |
| 39634 |
SnirBroshi author:SnirBroshi |
feat(LinearAlgebra/Matrix/Nondegenerate): more API and generalize to non-domains |
- Syntactically generalize the bilinear form identities to non-square matrices
- Prove iff and transpose theorems for `SeparatingLeft`/`SeparatingRight`/`Nondegenerate`
- Prove `M *ᵥ v = 0 → v = 0` and `v ᵥ* M = 0 → v = 0` given `Nondegenerate`
(extracted from the existing `eq_zero_of_*_eq_zero`)
- Generalize `M.det ≠ 0 → M.Nondegenerate` to `M.det ∈ R⁰ → M.Nondegenerate` (over any `CommRing`)
- Add `M *ᵥ v = 0 → v = 0` and `v ᵥ* M = 0 → v = 0` theorems given `M.det ∈ R⁰`
- Allow `NonUnitalNonAssocSemiring`s in the `def`s
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
130/44 |
Mathlib/Data/Matrix/Mul.lean,Mathlib/LinearAlgebra/Matrix/Nondegenerate.lean,Mathlib/LinearAlgebra/Matrix/ToLinearEquiv.lean |
3 |
9 |
['SnirBroshi', 'github-actions', 'themathqueen'] |
nobody |
4-81678 4 days ago |
4-81529 4 days ago |
9-7115 9 days |
| 39774 |
Hagb author:Hagb |
feat(Order/WellFounded): `WellFounded` on subtype iff the relation restricted on the subtype is `WellFounded` |
Equivalence between `WellFounded` on a subtype and `WellFounded` on the underlying type with the relation restricted on the subtype.
---
(It was a lemma for #39781, which has been closed since there would be a better proof.)
[](https://gitpod.io/from-referrer/)
|
t-order |
13/0 |
Mathlib/Order/WellFounded.lean |
1 |
3 |
['Hagb', 'SnirBroshi', 'github-actions'] |
nobody |
4-72937 4 days ago |
5-28209 5 days ago |
5-27978 5 days |
| 39214 |
Hagb author:Hagb |
refactor(Data/Finsupp/MonomialOrder): remove `.wf` (well foundedness) field from `MonomialOrder` |
Many properties still hold without the well-foundedness.
Although Gröbner basis theory requires the monomial order to be well founded for the termination of the division algorithm (formalized in `MonomialOrder.div`), many properties that don't relay on the division or remainder still hold without the well-foundedness.
Even the division algorithm can terminate in some cases where the monomial order isn't well founded. For example, if the divisors set is finite, then the algorithm can terminate w.r.t. `MonomialOrder.lex (σ := Nat)` even though it isn't well founded. Such cases cannot be directly stated if the formalization of monomial order requires well-foundedness.
Deletions:
- MonomialOrder.wf
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
21/13 |
Mathlib/Data/Finsupp/MonomialOrder.lean,Mathlib/Data/Finsupp/MonomialOrder/DegLex.lean,Mathlib/RingTheory/MvPolynomial/Groebner.lean,Mathlib/RingTheory/MvPolynomial/MonomialOrder/DegLex.lean |
4 |
5 |
['Hagb', 'github-actions', 'vihdzp'] |
nobody |
4-71524 4 days ago |
18-29657 18 days ago |
18-29426 18 days |
| 39808 |
chenson2018 author:chenson2018 |
chore(Data): refactor proofs where `grind?` fails |
These are sources of technical debt as now reported in the [weekly linting report](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Weekly.20linting.20log/with/544658968). The idea is that a successful `grind` proof can fail to report the theorems it used via `grind?`, which means that if these proofs break across toolchains that it becomes significantly harder to repair.
Most of these are fixed by squeezing the call to `grind` and unsetting `linter.tacticAnalysis.verifyGrindOnly` so they no longer appear in the weekly report. Unfortunately, this can't be on by default for performance reasons, but I highly encourage using this linter when adding any `grind` proofs.
---
[](https://gitpod.io/from-referrer/)
|
t-data
tech debt
|
69/41 |
Mathlib/Data/Bool/Basic.lean,Mathlib/Data/Bool/Set.lean,Mathlib/Data/EReal/Operations.lean,Mathlib/Data/Fin/Tuple/NatAntidiagonal.lean,Mathlib/Data/Finset/Image.lean,Mathlib/Data/Finset/Powerset.lean,Mathlib/Data/Finset/Range.lean,Mathlib/Data/Finset/SMulAntidiagonal.lean,Mathlib/Data/List/Basic.lean,Mathlib/Data/List/Chain.lean,Mathlib/Data/List/Count.lean,Mathlib/Data/List/Cycle.lean,Mathlib/Data/List/Induction.lean,Mathlib/Data/List/ReduceOption.lean,Mathlib/Data/List/Sigma.lean,Mathlib/Data/List/Sort.lean,Mathlib/Data/List/TakeDrop.lean,Mathlib/Data/List/Triplewise.lean,Mathlib/Data/Option/Basic.lean,Mathlib/Data/Set/Card.lean,Mathlib/Data/Set/Disjoint.lean,Mathlib/Data/Set/Function.lean,Mathlib/Data/Set/Insert.lean,Mathlib/Data/Sum/Order.lean |
24 |
1 |
['github-actions'] |
nobody |
4-60865 4 days ago |
4-74285 4 days ago |
4-74054 4 days |
| 39623 |
justus-springer author:justus-springer |
feat(Algebra/MvPolynomial/Basic): `coeff_C_of_ne_zero` and `coeff_add_single_C` |
These lemmas are multivariate analogs to `Polynomial.coeff_C_of_ne_zero`, `Polynomial.coeff_C_succ` and `PowerSeries.coeff_C_of_ne_zero` and `PowerSeries.coeff_succ_C`. They are useful for defining partial derivatives for multivariate power series, see PR #39626.
- [x] depends on: #39632
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
16/0 |
Mathlib/Algebra/MvPolynomial/Basic.lean,Mathlib/RingTheory/MvPowerSeries/Basic.lean |
2 |
7 |
['Hagb', 'github-actions', 'justus-springer', 'mathlib-dependent-issues', 'wwylele'] |
nobody |
4-60337 4 days ago |
4-62001 4 days ago |
9-25669 9 days |
| 35287 |
arnoudvanderleer author:arnoudvanderleer |
feat(AlgebraicTopology/SimplicialSet): define isomorphisms in simplicial sets, and the coherent isomorphism simplicial set |
show that any edge in a simplicial set, that is the image of the forward edge of the coherent isomorphism under a simplicial set morphism, is an isomorphism.
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-topology
new-contributor
infinity-cosmos
|
362/3 |
Mathlib.lean,Mathlib/AlgebraicTopology/SimplicialSet/CoherentIso.lean,Mathlib/AlgebraicTopology/SimplicialSet/CompStruct.lean,Mathlib/AlgebraicTopology/SimplicialSet/NerveCodiscrete.lean,Mathlib/AlgebraicTopology/SimplicialSet/StdSimplex.lean,Mathlib/CategoryTheory/CodiscreteCategory.lean |
6 |
124 |
['arnoudvanderleer', 'dagurtomas', 'github-actions', 'joelriou', 'mathlib-merge-conflicts', 'robin-carlier'] |
robin-carlier assignee:robin-carlier |
4-56702 4 days ago |
4-56702 4 days ago |
35-57403 35 days |
| 39769 |
chenson2018 author:chenson2018 |
chore(Topology): refactor proofs where `grind?` fails |
These are sources of technical debt as now reported in the [weekly linting report](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Weekly.20linting.20log/with/544658968). The idea is that a successful `grind` proof can fail to report the theorems it used via `grind?`, which means that if these proofs break across toolchains that it becomes significantly harder to repair.
Most of these are fixed by squeezing the call to `grind` and unsetting `linter.tacticAnalysis.verifyGrindOnly` so they no longer appear in the weekly report. Unfortunately, this can't be on by default for performance reasons, but I highly encourage using this linter when adding any `grind` proofs.
---
[](https://gitpod.io/from-referrer/)
|
t-topology
tech debt
|
35/17 |
Mathlib/Topology/Compactness/CountablyCompact.lean,Mathlib/Topology/EMetricSpace/BoundedVariation.lean,Mathlib/Topology/MetricSpace/Pseudo/Defs.lean,Mathlib/Topology/Order/Basic.lean,Mathlib/Topology/Order/IsLUB.lean,Mathlib/Topology/Order/WithTop.lean,Mathlib/Topology/Path.lean,Mathlib/Topology/Sets/VietorisTopology.lean,Mathlib/Topology/Sheaves/Flasque.lean |
9 |
1 |
['github-actions'] |
nobody |
4-50792 4 days ago |
5-49543 5 days ago |
5-49312 5 days |
| 38669 |
dannyply author:dannyply |
feat(Topology/Algebra/PontryaginDual): prove compact monoids have discrete duals |
Proves that the Pontryagin dual of a compact monoid is discrete. As a consequence, it also adds the corresponding finite-type instances for compact discrete monoids.
This upstreams a result first added downstream in [`YaelDillies/APAP`](https://github.com/YaelDillies/APAP), where this fact was needed to close a `sorry`. The proof separates the trivial character from all the others using the right half of the circle and adds a few reusable `Circle` helper lemmas near the existing related API.
The original APAP proof was AI-assisted and then reviewed/rewritten during downstream review. For this PR, I used Codex to help adapt the APAP proof to mathlib and to refactor the supporting lemmas.
---
[](https://gitpod.io/from-referrer/) |
t-topology
new-contributor
|
130/16 |
Mathlib/Analysis/SpecialFunctions/Complex/Circle.lean,Mathlib/Topology/Algebra/PontryaginDual.lean,Mathlib/Topology/MetricSpace/Pseudo/Defs.lean |
3 |
30 |
['dannyply', 'github-actions', 'j-loreaux', 'tb65536'] |
j-loreaux assignee:j-loreaux |
4-47057 4 days ago |
4-47057 4 days ago |
5-35505 5 days |
| 39820 |
samuelchassot author:samuelchassot |
Add proof of the existence of an Eulerian walk if all vertices have even degree or if exactly vertices have odd degree |
As per the TODO open in `Trails.lean`.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
671/3 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Eulerian.lean,Mathlib/Combinatorics/SimpleGraph/Trails.lean |
3 |
8 |
['SnirBroshi', 'copilot-pull-request-reviewer', 'github-actions'] |
nobody |
4-45899 4 days ago |
4-47130 4 days ago |
4-46899 4 days |
| 32583 |
MJ141592 author:MJ141592 |
refactor(SimpleGraph): change bridges not to require the edge to be present |
Remove the requirement for edges to exist in definition of isBridge, and then change the related lemmas to adjust for this, by renaming, fixing the statements and fixing the proofs, including in Acyclic.
Closes #31690.
---
- [x] depends on: #36802
- [x] depends on: #36804 |
t-combinatorics
new-contributor
|
95/93 |
Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/EdgeConnectivity.lean,Mathlib/Combinatorics/SimpleGraph/DeleteEdges.lean,Mathlib/Combinatorics/SimpleGraph/Hamiltonian.lean |
5 |
48 |
['MJ141592', 'Rida-Hamadani', 'SnirBroshi', 'YaelDillies', 'b-mehta', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot'] |
nobody |
4-43598 4 days ago |
4-43631 4 days ago |
53-85978 53 days |
| 39818 |
Ljon4ik4 author:Ljon4ik4 |
feat: Transferring Lie Algebra structures along Equivalences |
This pr adds the functionality to transfer Lie brackets along equivalences (additive, linear and plain ones).
I followed the scheme of the existing `TransferInstance.lean` file.
For one of the proofs, I also needed `linearEquiv_apply `, which seemed missing so I added it.
AI use disclaimer: I used claude to search for lemmas/ understand error messages / proofreading and feedback, but wrote the whole code myself.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
124/0 |
Mathlib.lean,Mathlib/Algebra/Lie/TransferInstance.lean,Mathlib/Algebra/Module/TransferInstance.lean |
3 |
2 |
['github-actions'] |
nobody |
4-43052 4 days ago |
4-43127 4 days ago |
4-45141 4 days |
| 37984 |
loefflerd author:loefflerd |
feat: abstract theory of measures |
General foundations of non-archimedean measure theory (intended for applications to Iwasawa algebras)
---
- [x] depends on: #38701 |
t-topology |
306/0 |
Mathlib.lean,Mathlib/NumberTheory/Padics/Measure/Basic.lean,Mathlib/NumberTheory/Padics/Measure/Topology.lean |
3 |
11 |
['github-actions', 'j-loreaux', 'loefflerd', 'mathlib-dependent-issues'] |
PatrickMassot assignee:PatrickMassot |
4-42185 4 days ago |
4-42185 4 days ago |
19-42773 19 days |
| 39736 |
NoahW314 author:NoahW314 |
feat(RingTheory/MvPolynomial/MonomialOrder): add `leadingTerm` lemmas |
Add lemmas for `leadingTerm` to match those for `leadingCoeff`.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
87/0 |
Mathlib/RingTheory/MvPolynomial/MonomialOrder.lean |
1 |
5 |
['Hagb', 'NoahW314', 'github-actions'] |
nobody |
4-41084 4 days ago |
6-81658 6 days ago |
6-81427 6 days |
| 39692 |
YaelDillies author:YaelDillies |
chore(Algebra/Order/BigOperators): follow the `₀` naming convention |
We have long agreed that `MonoidWithZero` lemmas corresponding to `Monoid` lemmas should be suffixed with `₀`, while currently it is the `Monoid` lemmas that are primed.
Also deprecate two primed lemmas that only differed from the unprimed versions in a minor way.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-order
label:t-algebra$ |
283/219 |
Mathlib/Algebra/BigOperators/Finprod.lean,Mathlib/Algebra/Group/Submonoid/Pointwise.lean,Mathlib/Algebra/Order/BigOperators/Group/Finset.lean,Mathlib/Algebra/Order/BigOperators/Group/List.lean,Mathlib/Algebra/Order/BigOperators/Group/Multiset.lean,Mathlib/Algebra/Order/BigOperators/GroupWithZero/Finset.lean,Mathlib/Analysis/Analytic/Composition.lean,Mathlib/Analysis/Asymptotics/SpecificAsymptotics.lean,Mathlib/Analysis/BoxIntegral/DivergenceTheorem.lean,Mathlib/Analysis/Complex/Exponential.lean,Mathlib/Analysis/Complex/JensenFormula.lean,Mathlib/Analysis/InnerProductSpace/Orientation.lean,Mathlib/Analysis/InnerProductSpace/Subspace.lean,Mathlib/Analysis/Normed/Ring/Basic.lean,Mathlib/Analysis/Normed/Ring/InfiniteProd.lean,Mathlib/Analysis/ODE/DiscreteGronwall.lean,Mathlib/Analysis/Polynomial/MahlerMeasure.lean,Mathlib/Analysis/SpecialFunctions/Trigonometric/Chebyshev/Extremal.lean,Mathlib/Analysis/SpecificLimits/Basic.lean,Mathlib/MeasureTheory/Constructions/Pi.lean,Mathlib/MeasureTheory/Measure/HasOuterApproxClosedProd.lean,Mathlib/MeasureTheory/Measure/Lebesgue/Basic.lean,Mathlib/MeasureTheory/Measure/Lebesgue/VolumeOfBalls.lean,Mathlib/NumberTheory/Bertrand.lean,Mathlib/NumberTheory/Height/Basic.lean,Mathlib/NumberTheory/Height/MvPolynomial.lean,Mathlib/NumberTheory/NumberField/InfinitePlace/Basic.lean,Mathlib/NumberTheory/Primorial.lean,Mathlib/NumberTheory/SelbergSieve.lean,Mathlib/NumberTheory/SiegelsLemma.lean,Mathlib/NumberTheory/SmoothNumbers.lean,Mathlib/Probability/ProductMeasure.lean,Mathlib/RingTheory/Polynomial/Cyclotomic/Eval.lean,Mathlib/Topology/Algebra/InfiniteSum/ENNReal.lean,Mathlib/Topology/Algebra/InfiniteSum/Order.lean |
35 |
4 |
['github-actions', 'mathlib-merge-conflicts', 'vihdzp'] |
nobody |
4-40625 4 days ago |
4-40660 4 days ago |
5-69519 5 days |
| 39829 |
or4nge19 author:or4nge19 |
feat(LinearAlgebra): basis flag lemmas and genEigenspace map |
Part 1/3 of #39139.
Introduces basis flag lemmas and intertwining `genEigenspace` map, using directly available constructors, ie introducing none (so improving on #39139)
Co-authored-by: [kuotsanhsu](https://github.com/kuotsanhsu) [learningstud@gmail.com](mailto:learningstud@gmail.com)
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
large-import
label:t-algebra$ |
76/2 |
Mathlib/LinearAlgebra/Basis/Flag.lean,Mathlib/LinearAlgebra/Eigenspace/Basic.lean |
2 |
1 |
['github-actions'] |
nobody |
4-38891 4 days ago |
4-38949 4 days ago |
4-38745 4 days |
| 39815 |
sharky564 author:sharky564 |
feat(Analysis/Normed/Module/Complemented): add `IsCompl.isTopCompl_of_isClosed` and `isTopCompl_iff_isCompl_isClosed_isClosed` |
Adds two theorems:
- `IsCompl.isTopCompl_of_isClosed`: In a Banach space, two closed submodules that are algebraic complements are topological
- `isTopCompl_iff_isCompl_isClosed_isClosed`: `p` and `q` are topological complements if and only if `p` and `q` are algebraic complements and `p` and `q` are both closed.
---
This PR addresses the final point of #38416, and finally close it. However, this is no longer much of a refactor as it is more just adding these theorems in. |
t-analysis |
14/1 |
Mathlib/Analysis/Normed/Module/Complemented.lean |
1 |
3 |
['github-actions', 'themathqueen'] |
nobody |
4-38525 4 days ago |
4-51427 4 days ago |
4-51196 4 days |
| 39745 |
joneugster author:joneugster |
feat: install gh inside the devcontainer |
* Install `gh` automatically in the dev container, try to login on startup.
* Mount local `.gitconfig` in the container. This allows access to the globally configured git user name and such.
The motivation behind this PR is to provide a simple way of sandboxing PRs during review. In particular, keeping the .olean files, which originate from an untrusted fork, contained. During review, `gh pr checkout` is defacto a required tool.
Other tools like [bubble](https://github.com/kim-em/bubble#bubble) aim to address the same use case. However, vscode devcontainer are more mature and the setup is done with few lines of code, easy to understand.
---
### LLM usage
The line
```text
source=${localEnv:HOME}/.gitconfig,target=/home/vscode/.gitconfig,type=bind,consistency=cached
```
has been suggested by querying an LLM. It looks like this is what literature online seems to be using:
* https://github.com/microsoft/vscode/issues/265651
* https://marcandreuf.com/blog/2024-07-12-gitdevcont/
[](https://gitpod.io/from-referrer/)
|
CI |
14/1 |
.devcontainer/devcontainer.json,.gitignore |
2 |
1 |
['github-actions'] |
bryangingechen assignee:bryangingechen |
4-33415 4 days ago |
4-33652 4 days ago |
6-49271 6 days |
| 34909 |
SnirBroshi author:SnirBroshi |
feat(Data/Sym/Sym2): `fromRel` equivalence with `Sigma` over a `Quotient` |
Add a non-dependent recursor on members of a `fromRel` set, and the following `Equiv`s:
- The `fromRel` set of a symmetric relation `r` is equivalent to summing that set restricted to fibers of `f`.
- For a relation homomorphism `r →r r'` where `r` is symmetric, the `fromRel` set of `r` is equivalent to summing that set restricted to equivalence classes of `r'` using a `Subtype`.
---
I find this recursor pretty useful when dealing with `fromRel`, the idea came from a suggestion by @kmill [on Zulip](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Eq.2Erec.20with.20a.20constant.20does.20nothing.3A.20h.20.E2.96.B8.20c.20.3D.20c/near/565176948) for another `Sym2` conundrum.
[](https://gitpod.io/from-referrer/)
|
t-data
maintainer-merge
|
55/3 |
Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Data/Sym/Sym2.lean |
2 |
19 |
['SnirBroshi', 'bryangingechen', 'chrisflav', 'eric-wieser', 'github-actions', 'mathlib-bors', 'mathlib-merge-conflicts'] |
eric-wieser assignee:eric-wieser |
4-31944 4 days ago |
4-31944 4 days ago |
86-66716 86 days |
| 38488 |
b-mehta author:b-mehta |
feat(Data/Finset/Card): iterating a function's image on a finite set stabilises |
...and does so in a bounded number of steps (which is why this is Finset-specific).
In a later PR, I'll add this for endofunctions on a fintype, as well as add a Set.Finite version.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
35/0 |
Mathlib/Data/Finset/Card.lean,Mathlib/Data/Finset/Image.lean |
2 |
17 |
['SnirBroshi', 'b-mehta', 'github-actions'] |
joneugster assignee:joneugster |
4-31031 4 days ago |
4-31115 4 days ago |
35-6277 35 days |
| 38245 |
RemyDegenne author:RemyDegenne |
feat: CountableSupClosed |
Define the property for a set of being closed by countable supremum (resp. infimum).
The new file is adapted from the `SupClosed` file, which describes sets closed by binary supremum.
Also use `to_dual` on `SupClosed`.
`CountableInfClosed` will be used in measure theory, for developments related to compact systems used for Kolmogorov's extension theorem and Choquet's capacitability theorem.
---
[](https://gitpod.io/from-referrer/)
|
t-order
brownian
|
381/66 |
Mathlib.lean,Mathlib/Order/CountableSupClosed.lean,Mathlib/Order/SupClosed.lean |
3 |
16 |
['RemyDegenne', 'b-mehta', 'github-actions', 'vihdzp'] |
nobody |
4-23267 4 days ago |
4-39840 4 days ago |
40-52050 40 days |
| 37179 |
IvanRenison author:IvanRenison |
feat(Combinatorics/SimpleGraph): add lemmas about left and right elements of `SimpleGraph.sum` |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
19/0 |
Mathlib/Combinatorics/SimpleGraph/Sum.lean |
1 |
5 |
['WilliamCoram', 'b-mehta', 'github-actions', 'mathlib-merge-conflicts'] |
b-mehta assignee:b-mehta |
4-23025 4 days ago |
4-23060 4 days ago |
64-19043 64 days |
| 39757 |
gasparattila author:gasparattila |
chore(Algebra/Star): clean up `simp` lemmas about bundled `star` equivalences |
This PR adds `.symm` lemmas for these equivalences, allowing `simp` to reduce applications of their inverses to applications of `star`.
---
[](https://gitpod.io/from-referrer/)
|
|
67/21 |
Mathlib/Algebra/Star/Basic.lean,Mathlib/Algebra/Star/Module.lean,Mathlib/Analysis/CStarAlgebra/Basic.lean,Mathlib/Topology/Algebra/Module/Star.lean |
4 |
2 |
['github-actions', 'themathqueen'] |
nobody |
4-21177 4 days ago |
6-21270 6 days ago |
6-21039 6 days |
| 36605 |
martinwintermath author:martinwintermath |
feat(Geometry/Convex/Cone): Add lemmas about interaction of hull, span and negation |
Prove lemmas about the interaction of hull, span and negation.
Main additions:
* `PointedCone.toSubmodule` that produces a submodule with the same support given that `-C = C`. Also the corresponding `CanLift`
* `PointedCone.hull_neg_pair_eq_span_singleton` proving `hull R {-x, x} = R ∙ x` (simp lemma)
* `PointedCone.span_eq_hull_neg_sup_hull` proving `span R s = hull R (-s) ⊔ hull R s`
* `PointedCone.mem_span` proving `x ∈ span R C ↔ ∃ p, n ∈ C, x = p - n`
Considerations: there are several ways to express that a convex cone is a submodule:
* `-C = C`
* `-C ≤ C` or `C ≤ -C`
* `C = span R C`
* `C = C.lineal`
The consensus was that the the first option is the most direct way to express this property, which then allows to lift to a submodule.
Co-authored by: Olivia Röhrig, Kilian Rueß, Artie Khovanov
---
- [x] depends on: #37464
[](https://gitpod.io/from-referrer/)
|
t-convex-geometry |
68/0 |
Mathlib/Geometry/Convex/Cone/Pointed.lean |
1 |
53 |
['artie2000', 'github-actions', 'martinwintermath', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
nobody |
4-19443 4 days ago |
4-19446 4 days ago |
21-19617 21 days |
| 37939 |
AntoineChambert-Loir author:AntoineChambert-Loir |
feat(Order/Completion): embed a linear order into a dense and complete linear order |
The aim of the PR is to prove the following theorem that will be used as an input to [Sion.DMCompletion.exists_isSaddlePointOn](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Topology/Sion.html#Sion.DMCompletion.exists_isSaddlePointOn) :
*If `β` is any linear order, then there exists a complete and dense linear order `γ` together with a continuous embedding `ι : β ↪o γ` (for the order topologies on `β` and `γ`).*
Meanwhile, the PR also records various instances about dense orders and lemmas regarding the Dedekind MacNeille completion and lexicographic orders.
---
[](https://gitpod.io/from-referrer/)
|
t-order |
211/4 |
Mathlib.lean,Mathlib/Data/Prod/Lex.lean,Mathlib/Order/Completion.lean,Mathlib/Topology/Order/Completion.lean,Mathlib/Topology/Sion.lean |
5 |
69 |
['ADedecker', 'AntoineChambert-Loir', 'YaelDillies', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp'] |
vihdzp assignee:vihdzp |
4-15149 4 days ago |
4-37975 4 days ago |
39-48581 39 days |
| 39747 |
vihdzp author:vihdzp |
feat: intervals `Ici`/`Ioi` are cofinal/closed under directed suprema |
---
[](https://gitpod.io/from-referrer/)
|
t-order |
67/11 |
Mathlib/Order/Cofinal.lean,Mathlib/Order/DirSupClosed.lean,Mathlib/Order/Interval/Set/Basic.lean,Mathlib/Order/UpperLower/Basic.lean,Mathlib/Topology/Order/ScottTopology.lean |
5 |
16 |
['YaelDillies', 'b-mehta', 'github-actions', 'vihdzp'] |
nobody |
4-14716 4 days ago |
5-37542 5 days ago |
6-15281 6 days |
| 39850 |
Ljon4ik4 author:Ljon4ik4 |
feat: Lie-Rinehart subalgebras introduced |
This PR introduces subalgebras of Lie-Rinehart algebras. It defines the corresponding structures, introduces some basic api and shows that a Lie-Rinehart subalgebra is again a Lie-Rinehart algebra.
Most of the code was copied and adapted from `Mathlib/Algebra/Lie/Subalgebra.lean`, however I am not aware of a way to reuse the results from there without copy/pasting them. I also noticed a problem with the namespace of a few simp lemmas in `LieRinehartAlgebra/Defs.lean` and corrected it.
There are a few design decisions that I am not sure about:
* There is one structure, which only needs `[Module A L]` and `[LieRing L]` to be defined. Then additional properties are added along the file whenever needed. It is a little strange to have a `LieRinehartSubalgebra` of something which is not a `LieRinehartalgebra`, but I don't know what a better solution would be
* The structure only uses `A, L` and not `R`, so `R` has to be explicitly passed to the functions later in the file.
AI use disclaimer: I used claude to search for lemmas/ understand error messages / proofreading and feedback, but did not use it for generating the code.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
267/2 |
Mathlib.lean,Mathlib/Algebra/LieRinehartAlgebra/Defs.lean,Mathlib/Algebra/LieRinehartAlgebra/Subalgebra.lean |
3 |
1 |
['github-actions'] |
nobody |
4-14158 4 days ago |
4-14225 4 days ago |
4-14891 4 days |
| 39798 |
vihdzp author:vihdzp |
chore: use `notation3` for `Ordinal.typeLT` |
This creates a delaborator, which avoids goals from looking like `(type fun x1 x2 ↦ x1 < x2) < (type fun x1 x2 ↦ x1 < x2)`.
---
[](https://gitpod.io/from-referrer/)
|
t-set-theory
easy
maintainer-merge
|
5/1 |
Mathlib/SetTheory/Ordinal/Basic.lean |
1 |
4 |
['YaelDillies', 'github-actions', 'vihdzp'] |
YaelDillies assignee:YaelDillies |
4-12866 4 days ago |
4-13475 4 days ago |
4-31043 4 days |
| 39856 |
b-mehta author:b-mehta |
feat(Data/Set/Restrict): extend is injective on the range |
These lemmas are placed here since that puts them close to the other `extend` lemmas, but they can't be in Logic/Function/Basic since InjOn and Set.range aren't defined there yet
---
[](https://gitpod.io/from-referrer/)
|
t-data |
15/0 |
Mathlib/Data/Set/Restrict.lean |
1 |
1 |
['github-actions'] |
nobody |
4-5514 4 days ago |
4-5589 4 days ago |
4-5358 4 days |
| 39561 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Operations): a graph is the supremum of edge graphs |
- `G = ⨆ e ∈ G.edgeSet, fromEdgeSet {e}`
- `G = sSup { edge u v | (u : V) (v : V) (_ : G.Adj u v) }`
and `edgeSet` & `fromEdgeSet` preserve sup & inf.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
51/0 |
Mathlib/Combinatorics/SimpleGraph/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Operations.lean |
2 |
2 |
['b-mehta', 'github-actions'] |
nobody |
4-5132 4 days ago |
10-74320 10 days ago |
10-74089 10 days |
| 39505 |
dannyhe652 author:dannyhe652 |
feat(SimpleGraph): add Vizing's theorem for edge coloring |
Hi! I'm a high school student interested in formulization of mathematics in Lean. Recently, I have worked on a project to formulize Vizing Theorem with Daniel Raggi from Cambridge University with AI assistance. In particular, we first drafted an outline for the proof, and built the proof using Claude Opus 4.5 and 4.6. The proof is optimized using Aristotle and finally reviewed by ourselves. We rewrote some parts of the code and some comments. The code now builds cleanly and we wish this code to be reviewed by Lean Community. I am aware that there are previous attempts, some being successful, on formulizing Vizing Theorem, including this one by Arohee https://github.com/aroheebhoja/vizing. However, I believe that no PR have been made. Our proof is not based on his proof, but it could be helpful for the community to review that project as well. I sincerely thank everyone who has time to verify and review our code. A summary of the project is as follows. Please contact me if there are any questions or problems.
## Summary
This PR completes the proof of **Vizing's theorem** for edge coloring in simple graphs, proving that the chromatic index of any graph is either Δ (the maximum degree) or Δ + 1.
## Changes
### New files
- **`Mathlib/Combinatorics/SimpleGraph/Coloring/EdgeColoring.lean`** — Core definitions
- `edgeColoring`: Type for line graph colorings
- `edgeColorable`: Graph is edge-colorable with n colors
- `chromaticIndex`: Chromatic index as ℕ
- **`Mathlib/Combinatorics/SimpleGraph/Coloring/KempeChain.lean`** — Kempe Chain
- Coloring observables: `incidentEdges`, `incidentColors`, `missingColors`
- Kempe subgraph structure with bounded degree
- `swapKempe`: Recolor edges in a connected component via color-swapping
- **`Mathlib/Combinatorics/SimpleGraph/Coloring/VizingFan.lean`** — Vizing Fan Rotation
- `IsFan`: Vizing fan structure with special color properties
- Fan maximality and dichotomy on terminal vertices
- `rotate_termA`: Extend coloring when a free color exists at both endpoints
- `vizingAdjacencyLemma`: Main adjacency lemma for both cases
- **`Mathlib/Combinatorics/SimpleGraph/Coloring/VizingTheorem.lean`** — Main theorems
- `edge_eq_of_color_eq`: Proper edge colorings assign different colors to distinct edges sharing a vertex
- `maxDegree_le_chromaticIndex`: χ'(G) ≥ Δ(G)
- `chromaticIndex_bot`: Empty graph has chromatic index 0
- `vizingUpperBound_aux`: Inductive proof of upper bound on number of edge
- `vizingTheorem`: χ'(G) ∈ {Δ(G), Δ(G) + 1}
### Modified files
- `Mathlib.lean` — Added imports for the four new coloring modules
## Technical Approach
**Lower bound** (χ'(G) ≥ Δ):
- Edges incident to a max-degree vertex form a clique in the line graph
- Clique number lower-bounds chromatic number
**Upper bound** (χ'(G) ≤ Δ + 1):
- Induction on the number of edges
- Base case: empty graph colored with 0 colors
- Inductive step:
- If a free color exists at both endpoints of an edge, then extend directly
- Otherwise:
- Build a maximal fan from one endpoint
- Apply dichotomy: either extend via Term-A (free color at both endpoints) or Term-B (Kempe swap)
- Term-B uses a three-vertex connectivity argument to derive a contradiction, forcing the fan to extend
## Key Lemmas
- `incidentEdges`, `incidentColors`, `missingColors`: Coloring observables at vertices
- `kempeSubgraph`: Restricted subgraph of edges with two specific colors
- `swapKempe`: Recolor via Kempe chain swapping
- `IsFan.singleton`: Trivial fan always valid
- `IsFan.length_le_card`: Fan length is bounded by vertex count
- `IsFan.dichotomy`: Maximal fan satisfies Term-A or Term-B
- `IsFan.rotate_termA`: Term-A case extends the coloring inductively
- `vizingAdjacencyLemma`: Handles both cases for extending one edge
- `vizingUpperBound_aux`: Framework for full inductive proof
- `edge_eq_of_color_eq`: Distinctness of edges with same color
## Testing
All four modules compile with no `sorry` nor errors or warnings.
## References
* V. G. Vizing, *On an estimate of the chromatic class of a p-graph*,
Diskret. Analiz. 3 (1964), 25–30.
## Co-authors
Co-authored-by: Daniel Raggi
Co-authored-by: Aristotle (Harmonic)
Co-authored-by: Claude Opus 4.5 & 4.6
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
LLM-generated
|
1915/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/EdgeColoring.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/KempeChain.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/VizingFan.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/VizingTheorem.lean |
5 |
3 |
['github-actions'] |
nobody |
4-5044 4 days ago |
12-6805 12 days ago |
12-7953 12 days |
| 39792 |
vihdzp author:vihdzp |
chore: deprecate `Ordinal.IsAcc` and `Ordinal.IsClosedBelow` |
These predicates were introduced in #16710 as preliminaries for a development of club sets. Those have [since been defined](https://leanprover-community.github.io/mathlib4_docs/Mathlib/SetTheory/Cardinal/Cofinality/Club.html#IsClub) without them, so we deprecate them, and generalize the results on them to the setting of successor orders.
---
[](https://gitpod.io/from-referrer/)
|
t-set-theory |
64/37 |
Mathlib/SetTheory/Ordinal/Topology.lean,Mathlib/Topology/Order/SuccPred.lean |
2 |
2 |
['github-actions', 'mathlib-bors'] |
nobody |
4-2772 4 days ago |
4-82689 4 days ago |
5-16217 5 days |
| 33313 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Coloring/Edge): create a basic edge-coloring API |
Module name decided on [Zulip](https://leanprover.zulipchat.com/#narrow/channel/252551-graph-theory/topic/Coloring.20module.20names/with/583281500).
---
Future work (which I'm working on):
- Relating degrees to edge-colorability (`G.maxDegree ≤ G.chromaticIndex`, `G.EdgeColorable 1 ↔ G.maxDegree ≤ 1`, `G.chromaticIndex = 1 ↔ G.maxDegree = 1`, `G.EdgeColorable 2 ↔ G.maxDegree ≤ 2`, `G.chromaticIndex = 2 ↔ G.maxDegree = 2`)
- [Vizing's theorem](https://en.wikipedia.org/wiki/Vizing%27s_theorem) (`G.chromaticIndex ≤ G.maxDegree + 1`)
- `chromaticIndex ⊤ = (if Even #V then #V - 1 else #V)`
- `[Infinite α] → chromaticIndex ⊤ = ⊤`
- [x] depends on: #33292
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
300/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/Edge.lean |
2 |
28 |
['SnirBroshi', 'YaelDillies', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'ooovi'] |
b-mehta assignee:b-mehta |
4-1215 4 days ago |
29-31467 29 days ago |
66-72570 66 days |
| 39178 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Measure/PreVariation` |
- refactors `Mathlib/MeasureTheory/Measure/PreVariation` by simplifying `sum_le'` and `sum_le_preVariationFun_of_subset`
Extracted from #38104
[](https://gitpod.io/from-referrer/)
|
codex
LLM-generated
t-measure-probability
|
6/20 |
Mathlib/MeasureTheory/Measure/PreVariation.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
sgouezel assignee:sgouezel |
4-1213 4 days ago |
18-62815 18 days ago |
18-62584 18 days |
| 39282 |
Sfgangloff author:Sfgangloff |
feat(SymbolicDynamics): add union morphism lemma for LanguageOn |
In symbolic dynamics.
This PR proves that taking the language over a finite shape commutes with unions of configuration sets:
$LanguageOn (X \cup Y) U = LanguageOn X U \cup LanguageOn Y U$
The proof is a direct unfolding of definitions: a pattern in the language of $X \cup Y$ comes from restricting a configuration $x ∈ X \cup Y$, and splitting on whether $x \in X$ or $x \in Y$ yields the corresponding inclusion in either $LanguageOn X U$ or $LanguageOn Y U$. The converse direction rebuilds a witness in $X \cup Y$ from either side of the union.
Related to issue #39252 |
t-dynamics
new-contributor
|
15/1 |
Mathlib/Dynamics/SymbolicDynamics/Basic.lean |
1 |
2 |
['github-actions'] |
sgouezel assignee:sgouezel |
4-1212 4 days ago |
16-65228 16 days ago |
16-64997 16 days |
| 39782 |
robin-carlier author:robin-carlier |
feat(Tactic): `nonempty` attribute |
This PR adds a `nonempty` attribute. When tagging a definition of type `α` with `[nonempty]`, an instance of type `Nonempty α` is automatically generated and registered using the definition.
Such an attribute is useful in the following scenario: certain structures are not classes (e.g., to avoid data-carrying classes potentially creating diamonds), but mere existence of terms of such structures allows to derive instances about the parameters of the structure. Using `[nonempty]` lets one auto-generate the instances derived instance (provided they correctly follow from `[Nonempty _]`).
Such is the case for the `CategoryTheory.Functor.FullyFaithful` structure, which allows to derive the `Prop`-classes `CategoryTheory.Functor.Full` and `CategoryTheory.Functor.Faithful`. Currently in mathlib, most definitions of type `CategoryTheory.Functor.FullyFaithful` are immediately followed by the corresponding `Full` and `Faithful` instances, adding "boilerplate" and increasing the surface for potential mistakes (like forgetting one or both of the instances.)
The attribute uses a variation of `addRelatedDecl` called `addRelatedInstance`, which handles automatic name generation and registration of instances from a given declaration and a "constructor" of type `Expr → List Name → MetaM (Expr × List Name)`.
---
I believe abstracting `addRelatedInst` might have other possible usages: for instance, given an adjunction `adj: L ⊣ R`, it would be nice to have an attribute that one can tag on such adjunctions that automatically registers `L.IsLeftAdjoint` and `R.IsRightAdjoint`. The `nonempty` attribute here can’t really do this because `R` can’t be inferred from a goal of type `L.IsLeftAdjoint`, but the situation is quite similar, and `addRelatedInst` could also help writing this kind of attribute.
[](https://gitpod.io/from-referrer/)
|
t-meta |
320/0 |
Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/NonemptyAttr.lean,Mathlib/Util/AddRelatedDecl.lean,MathlibTest/NonemptyAttr.lean |
5 |
1 |
['github-actions'] |
dwrensha assignee:dwrensha |
4-1208 4 days ago |
4-19052 4 days ago |
4-18821 4 days |
| 39809 |
zcyemi author:zcyemi |
feat(LinearAlgebra/AffineSpace/Menelaus): add Menelaus' theorem |
Add Menelaus' theorem for both `AffineSpace` and `NormedAddTorsor`.
The `AffineSpace` version includes both the forward and converse directions, while the `NormedAddTorsor` version currently includes the forward direction.
For the converse direction in the `NormedAddTorsor` setting, I am still considering the most convenient formalization for future use. One possible approach is to use `sbtw` / `¬ sbtw` to distinguish the different positional cases for points on the edges of a triangle, but this seems too complicated under permutations of the triangle vertices.
|
t-euclidean-geometry |
218/0 |
Mathlib.lean,Mathlib/Analysis/Normed/Affine/Menelaus.lean,Mathlib/LinearAlgebra/AffineSpace/Menelaus.lean,docs/1000.yaml |
4 |
1 |
['github-actions'] |
jsm28 assignee:jsm28 |
4-1206 4 days ago |
4-65810 4 days ago |
4-66256 4 days |
| 39063 |
khwilson author:khwilson |
feat(Topology/Algebra/Module/LocallyConvex): a very nice basis of locally convex spaces |
In proving facts about locally convex spaces, you often work with a basis of the neighborhoods of 0 that are open, symmetric, convex, antitone, and have the property that `V (n + 1) + V (n + 1) ⊆ V n` and `closure (V (n + 1)) ⊆ V n`.
These lemmas construct such a basis.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
137/30 |
Mathlib/Analysis/LocallyConvex/AbsConvex.lean,Mathlib/Topology/Algebra/Group/Pointwise.lean,Mathlib/Topology/Algebra/Module/LocallyConvex.lean |
3 |
10 |
['github-actions', 'j-loreaux', 'khwilson'] |
j-loreaux assignee:j-loreaux |
3-83017 3 days ago |
3-83086 3 days ago |
15-49207 15 days |
| 39722 |
kg583 author:kg583 |
feat(Combinatorics): Link `Nat.Partition` to `YoungDiagram` |
---
AI disclosure: Claude was used to source some proof sketches.
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
large-import
|
120/4 |
Mathlib.lean,Mathlib/Combinatorics/Enumerative/Partition/Basic.lean,Mathlib/Combinatorics/Enumerative/Partition/Conjugate.lean,Mathlib/Combinatorics/Young/YoungDiagram.lean |
4 |
36 |
['NoahW314', 'github-actions', 'kg583', 'wwylele'] |
nobody |
3-80925 3 days ago |
6-21734 6 days ago |
7-19078 7 days |
| 26212 |
Thmoas-Guan author:Thmoas-Guan |
feat(Algebra): the Rees theorem for depth |
In this PR we proved the Rees theorem for depth.
Co-authored-by: Hu Yongle
---
- [x] depends on: #37355
- [x] depends on: #38613
- [x] depends on: #38466
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
218/26 |
Mathlib.lean,Mathlib/RingTheory/Depth/Rees.lean,Mathlib/RingTheory/Regular/LinearMap.lean,docs/references.bib |
4 |
61 |
['Thmoas-Guan', 'alreadydone', 'chrisflav', 'dagurtomas', 'erdOne', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot'] |
chrisflav assignee:chrisflav |
3-75634 3 days ago |
4-50942 4 days ago |
99-44927 99 days |
| 39789 |
vihdzp author:vihdzp |
feat: a cofinal set has a cofinal subset of order type `(cof α).ord` |
---
[](https://gitpod.io/from-referrer/)
|
t-set-theory
maintainer-merge
|
38/20 |
Mathlib/SetTheory/Cardinal/Aleph.lean,Mathlib/SetTheory/Cardinal/Cofinality/Basic.lean,Mathlib/SetTheory/Cardinal/Cofinality/Ordinal.lean,Mathlib/SetTheory/Ordinal/Basic.lean |
4 |
7 |
['YaelDillies', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp'] |
nobody |
3-70698 3 days ago |
3-72458 3 days ago |
5-2899 5 days |
| 38275 |
TTony2019 author:TTony2019 |
feat: Add `AffineEquiv.image_intrinsicInterior` |
## Summary
This PR generalizes the existing lemma `AffineIsometry.image_intrinsicInterior` to the setting of affine equivalences, yielding the corresponding result `AffineEquiv.image_intrinsicInterior`.
Since affine equivalences are more general than affine isometries, the proof requires an additional finite-dimensionality assumption. The key extra input is that in finite-dimensional spaces, an affine equivalence induces a homeomorphism via `AffineEquiv.toHomeomorphOfFiniteDimensional`, so the assumptions are adjusted accordingly.
Apart from these extra assumptions, the argument is essentially the same as for `AffineIsometry.image_intrinsicInterior`.
## Collaboration
This PR was developed together with @imathwy.
|
t-analysis
new-contributor
|
283/41 |
Mathlib/Analysis/Convex/Intrinsic.lean,Mathlib/Analysis/Normed/Module/FiniteDimension.lean,Mathlib/LinearAlgebra/AffineSpace/Restrict.lean,Mathlib/Topology/Algebra/AffineSubspace.lean,Mathlib/Topology/Homeomorph/Defs.lean |
5 |
29 |
['TTony2019', 'github-actions', 'imathwy', 'j-loreaux', 'themathqueen'] |
j-loreaux assignee:j-loreaux |
3-62351 3 days ago |
3-62351 3 days ago |
20-52803 20 days |
| 39491 |
Yu-Misaka author:Yu-Misaka |
feat(Mathlib/LinearAlgebra/RootSystem/CartanMatrix): a Cartan matrix of a reduced crystallographic root system cannot have eigenvalue 4 |
This proves the TODO that a Cartan matrix of a reduced crystallographic root system cannot have eigenvalue 4.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-algebra
codex
LLM-generated
label:t-algebra$ |
125/8 |
Mathlib/Data/Matrix/Mul.lean,Mathlib/LinearAlgebra/RootSystem/CartanMatrix.lean,Mathlib/LinearAlgebra/RootSystem/GeckConstruction/Basis.lean,Mathlib/LinearAlgebra/RootSystem/GeckConstruction/Semisimple.lean |
4 |
6 |
['Yu-Misaka', 'copilot-pull-request-reviewer', 'github-actions', 'mathlib-bors', 'ocfnash'] |
ocfnash assignee:ocfnash |
3-59435 3 days ago |
3-59524 3 days ago |
3-59303 3 days |
| 37697 |
IvanRenison author:IvanRenison |
feat(Combinatorics/SimpleGraph/Clique): add theorems about cliques and induced graphs |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
maintainer-merge
|
22/0 |
Mathlib/Combinatorics/SimpleGraph/Clique.lean |
1 |
11 |
['Rida-Hamadani', 'SnirBroshi', 'YaelDillies', 'github-actions'] |
nobody |
3-58853 3 days ago |
4-23049 4 days ago |
48-24175 48 days |
| 39693 |
yuanyi-350 author:yuanyi-350 |
feat(Combinatorics/Enumerative/Bell): sum over partition shapes |
Kill TODO in `Mathlib/Combinatorics/Enumerative/Bell.lean` which proves `Nat.bell` as a sum of `Multiset.bell` over partition shapes
---
Migrated from #37690
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
maintainer-merge
|
128/35 |
Mathlib/Combinatorics/Enumerative/Bell.lean |
1 |
6 |
['YaelDillies', 'github-actions'] |
nobody |
3-57366 3 days ago |
7-53077 7 days ago |
7-52846 7 days |
| 39740 |
Thmoas-Guan author:Thmoas-Guan |
feat(FieldTheory): the field of adjoining all `p`th roots |
In this PR, we define the field extension of adjoining all `p`th roots to a field of characteristic `p`.
The definition is via defining it as the field itself with algebra map equal to frobenious. Thanks to @erdOne for this idea.
Co-authored by:@dleijnse
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
65/0 |
Mathlib.lean,Mathlib/FieldTheory/PurelyInseparable/AdjoinPthRoots.lean |
2 |
47 |
['Thmoas-Guan', 'chrisflav', 'erdOne', 'plp127', 'vihdzp'] |
chrisflav assignee:chrisflav |
3-53904 3 days ago |
4-32951 4 days ago |
6-58387 6 days |
| 37934 |
Thmoas-Guan author:Thmoas-Guan |
feat(FieldTheory): definition of transcendental separable field extension |
In this PR, we introduce the concept of separably generated field extension and transcendental separable field extension.
Further properties will be in #37838
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
102/0 |
Mathlib.lean,Mathlib/FieldTheory/TranscendentalSeparable.lean |
2 |
14 |
['Thmoas-Guan', 'robin-carlier'] |
robin-carlier assignee:robin-carlier |
3-53733 3 days ago |
19-39959 19 days ago |
27-57905 27 days |
| 28683 |
Thmoas-Guan author:Thmoas-Guan |
feat(RingTheory): regular local ring is domain |
In this PR, we proved for a regular local ring `R`,
1 : for a finite set `S` in the maximal Ideal of `R`, it can be extended to a regular system of parameters iff they are linear independent in the cotangent space iff `R/span S` is regular local ring of dimesion `dim R - |S|`
2 : is domain
3 : regular system of parameter form regular sequence.
---
- [x] depends on: #28682
- [x] depends on: #37627
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
323/0 |
Mathlib.lean,Mathlib/Algebra/Module/SpanRank.lean,Mathlib/RingTheory/Ideal/Height.lean,Mathlib/RingTheory/Ideal/Operations.lean,Mathlib/RingTheory/RegularLocalRing/Basic.lean |
5 |
58 |
['Raph-DG', 'Thmoas-Guan', 'WenrongZou', 'erdOne', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot', 'mbkybky'] |
nobody |
3-51840 3 days ago |
6-59792 6 days ago |
8-35266 8 days |
| 39600 |
plp127 author:plp127 |
chore(Topology/Compactness/CountablyCompact): generalize theorem |
Generalize theorem `Topology.IsEmbedding.isSeqCompact_iff` to `Topology.IsInducing.isSeqCompact_iff` by replacing `IsEmbedding` by `IsInducing`.
Also fix capitalization error.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
10/4 |
Mathlib/Topology/Compactness/CountablyCompact.lean |
1 |
5 |
['grunweg', 'plp127', 'themathqueen'] |
nobody |
3-51126 3 days ago |
6-13212 6 days ago |
8-75940 8 days |
| 38950 |
smmercuri author:smmercuri |
chore(Algebra): `coe_algHom` -> `coe_toAlgHom` |
---
There are also instances of `coe_ringHom`, `coe_linearMap` etc which I can fix in follow-up PRs
[](https://gitpod.io/from-referrer/)
|
|
78/64 |
Mathlib/Algebra/Algebra/Equiv.lean,Mathlib/Algebra/Algebra/Spectrum/Basic.lean,Mathlib/Algebra/Algebra/Subalgebra/Centralizer.lean,Mathlib/Algebra/Azumaya/Basic.lean,Mathlib/Algebra/MvPolynomial/Equiv.lean,Mathlib/AlgebraicGeometry/AffineSpace.lean,Mathlib/Analysis/CStarAlgebra/GelfandDuality.lean,Mathlib/FieldTheory/Extension.lean,Mathlib/FieldTheory/Galois/Basic.lean,Mathlib/FieldTheory/Isaacs.lean,Mathlib/FieldTheory/KummerExtension.lean,Mathlib/FieldTheory/LinearDisjoint.lean,Mathlib/FieldTheory/Minpoly/Field.lean,Mathlib/FieldTheory/SeparableDegree.lean,Mathlib/FieldTheory/SeparablyGenerated.lean,Mathlib/LinearAlgebra/Charpoly/Basic.lean,Mathlib/LinearAlgebra/TensorProduct/Subalgebra.lean,Mathlib/NumberTheory/Cyclotomic/Gal.lean,Mathlib/RingTheory/Algebraic/MvPolynomial.lean,Mathlib/RingTheory/Bialgebra/Equiv.lean,Mathlib/RingTheory/Bialgebra/Hom.lean,Mathlib/RingTheory/DividedPowerAlgebra/Init.lean,Mathlib/RingTheory/Extension/Presentation/Basic.lean,Mathlib/RingTheory/Extension/Presentation/Core.lean,Mathlib/RingTheory/GradedAlgebra/AlgHom.lean,Mathlib/RingTheory/GradedAlgebra/TensorProduct.lean,Mathlib/RingTheory/Ideal/Quotient/Operations.lean,Mathlib/RingTheory/MvPolynomial/Symmetric/FundamentalTheorem.lean,Mathlib/RingTheory/NoetherNormalization.lean,Mathlib/RingTheory/Polynomial/Cyclotomic/Factorization.lean,Mathlib/RingTheory/Smooth/Basic.lean,Mathlib/RingTheory/Smooth/IntegralClosure.lean,Mathlib/RingTheory/TensorProduct/Maps.lean |
33 |
6 |
['github-actions', 'j-loreaux', 'mathlib-merge-conflicts'] |
nobody |
3-43424 3 days ago |
3-43465 3 days ago |
19-36991 19 days |
| 26304 |
Raph-DG author:Raph-DG |
feat(AlgebraicGeometry): Pushforward of algebraic cycles |
In this PR we define a notion of the "pushfoward of functions with locally finite support". We give this PR the suggestive title "pushforward of algebraic cycles" because we will go on to model algebraic cycles on a scheme X as functions from X to the integers with locally finite support.
- [x] depends on: #26225
- [x] depends on: #26259
- [x] depends on: #35807
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-geometry
maintainer-merge
|
91/0 |
Mathlib.lean,Mathlib/Topology/LocallyFinsupp.lean,Mathlib/Topology/LocallyFinsupp/Pushforward.lean |
3 |
63 |
['Raph-DG', 'chrisflav', 'github-actions', 'joelriou', 'leanprover-community-bot-assistant', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
joelriou assignee:joelriou |
3-42747 3 days ago |
3-42893 3 days ago |
46-1658 46 days |
| 39870 |
YaelDillies author:YaelDillies |
feat(Data): interleaving lists |
Define interleaving of lists, both as an operation and as a relation.
This will be used to define interleaving polynomials, which in turn are a central concept in the line of work that earned June Huh his 2022 Fields medal.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
119/0 |
Mathlib.lean,Mathlib/Data/List/Interleave.lean |
2 |
1 |
['github-actions'] |
nobody |
3-39288 3 days ago |
3-39354 3 days ago |
3-39557 3 days |
| 36814 |
YaelDillies author:YaelDillies |
refactor(Combinatorics/SimpleGraph): no proof obligation in `rotate` |
If the walk doesn't go through the new vertex, return `nil` instead.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
41/32 |
Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Subgraph.lean,Mathlib/Combinatorics/SimpleGraph/Hamiltonian.lean,Mathlib/Combinatorics/SimpleGraph/Matching.lean,Mathlib/Combinatorics/SimpleGraph/Paths.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Decomp.lean |
7 |
9 |
['SnirBroshi', 'YaelDillies', 'b-mehta', 'eric-wieser', 'github-actions', 'mathlib-merge-conflicts'] |
nobody |
3-38041 3 days ago |
3-38118 3 days ago |
65-76002 65 days |
| 39864 |
8e7 author:8e7 |
feat(Combinatorics/SimpleGraph/Acyclic): helly property on subtrees |
This PR adds several lemmas regarding connected subsets of vertices in trees (subtrees). The main result is the Helly property for subtrees: For a finite set of subtrees, if any pair of subtrees intersect, then there is a common vertex in all subtrees.
This lemma is part of an effort to formalize tree decompositions (see #38334), and will be used in a future PR to prove `G.cliqueNum - 1 <= G.treeWidth`.
AI Usage: The proofs were developed with the help of Claude Code. I vouch for all the code written and understand the content fully.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
LLM-generated
|
114/0 |
Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Subgraph.lean |
2 |
2 |
['github-actions'] |
nobody |
3-37419 3 days ago |
3-58932 3 days ago |
3-58815 3 days |
| 33506 |
Rida-Hamadani author:Rida-Hamadani |
feat(SimpleGraph): construct a cycle of two distinct paths with same start and end |
Co-authored-by: Vlad Tsyrklevich
Co-authored-by: Snir Broshi <26556598+SnirBroshi@users.noreply.github.com>
---
- [x] depends on: #33249
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
maintainer-merge
|
110/5 |
Mathlib/Combinatorics/SimpleGraph/Paths.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Decomp.lean,Mathlib/Data/List/Basic.lean,Mathlib/Data/List/Nodup.lean |
5 |
62 |
['Rida-Hamadani', 'SnirBroshi', 'YaelDillies', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot', 'vlad902'] |
nobody |
3-36963 3 days ago |
3-37036 3 days ago |
34-72644 34 days |
| 34805 |
DavidLedvinka author:DavidLedvinka |
feat(Tactic): generalize ofScientific NormNum extension to `DivisionSemiring` |
Co-authored-by: @hrmacbeth |
t-meta
maintainer-merge
|
70/16 |
Mathlib/Algebra/Field/Rat.lean,Mathlib/Tactic/NormNum/Inv.lean,Mathlib/Tactic/NormNum/OfScientific.lean,MathlibTest/Tactic/NormNum/Basic.lean |
4 |
31 |
['DavidLedvinka', 'JovanGerb', 'b-mehta', 'eric-wieser', 'github-actions', 'mathlib-merge-conflicts', 'thorimur'] |
eric-wieser assignee:eric-wieser |
3-31050 3 days ago |
4-189 3 days ago |
89-60260 89 days |
| 39709 |
justus-springer author:justus-springer |
feat(RingTheory/): `MvPolynomial` is standard smooth |
Add the trivial submersive presentation for `MvPolynomial` and show that `MvPolynomial` is standard smooth over its base ring. This will be used to show that affine space is smooth in #39710.
- [x] depends on: #39708
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
47/0 |
Mathlib/RingTheory/Extension/Presentation/Basic.lean,Mathlib/RingTheory/Extension/Presentation/Submersive.lean,Mathlib/RingTheory/Smooth/StandardSmooth.lean |
3 |
3 |
['github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
nobody |
3-24903 3 days ago |
3-24911 3 days ago |
3-27569 3 days |
| 39110 |
SnirBroshi author:SnirBroshi |
chore(Data/Set): reduce defeq abuse of `Set α = α → Prop` |
These are among the first places that would fail if `Set α` wasn't defeq to `α → Prop`.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
35/20 |
Mathlib/Data/Set/Basic.lean,Mathlib/Data/Set/Defs.lean,Mathlib/Data/Set/Insert.lean,Mathlib/Data/Set/Prod.lean,Mathlib/Order/BooleanAlgebra/Set.lean |
5 |
24 |
['SnirBroshi', 'Vierkantor', 'github-actions', 'leanprover-radar', 'mathlib-bors', 'themathqueen', 'urkud', 'vihdzp'] |
urkud assignee:urkud |
3-23332 3 days ago |
13-57575 13 days ago |
19-58744 19 days |
| 39867 |
JovanGerb author:JovanGerb |
feat: `to_dual` for `Adjunction` |
This PR uses the new capability of `to_dual` to deal with universe reorderings to tag `Adjunction`.
`Adjunction.ext_counit` is added as the dual of `Adjunction.ext`.
This PR introduces 4 uses of `erw` to deal with defeq abuse. See https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/.5Bto_app.5D.20and.20associators.2Funitors/near/597924260
Note: there is a bug in the implementation that I'll have to fix which stops me from being able to tag `Adjunction.comp`.
---
[](https://gitpod.io/from-referrer/)
|
|
45/47 |
Mathlib/CategoryTheory/Adjunction/Basic.lean,Mathlib/CategoryTheory/Adjunction/FullyFaithful.lean,Mathlib/CategoryTheory/Sites/Sheafification.lean |
3 |
1 |
['github-actions'] |
nobody |
3-17406 3 days ago |
3-19582 3 days ago |
3-40159 3 days |
| 39863 |
thomaskwaring author:thomaskwaring |
feat(Topology/Sets/Opens): Heyting-algebra operations on open sets |
Add expressions for the Heyting-algebra operations on the frame of opens subsets of a topological space.
---
[](https://gitpod.io/from-referrer/)
|
t-topology
new-contributor
|
22/0 |
Mathlib/Topology/Sets/Opens.lean |
1 |
9 |
['eric-wieser', 'github-actions', 'thomaskwaring'] |
nobody |
3-9474 3 days ago |
3-55091 3 days ago |
3-62411 3 days |
| 39855 |
b-mehta author:b-mehta |
feat(InfiniteSum): zero function has product zero |
Prove that in a comm monoid with zero, the product of the zero function is zero.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
13/0 |
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean |
1 |
3 |
['b-mehta', 'github-actions', 'plp127'] |
nobody |
3-9252 3 days ago |
3-9298 3 days ago |
3-62307 3 days |
| 38600 |
khwilson author:khwilson |
feat(Topology/Semicontinuity): additional definitions for correspondences |
On the way to proving Michael's selection theorem, several extra notions related to hemicontinuity are introduced. Specifically, the notion of a correspondence having lower sections and it having an open graph.
The first construction is what is used in the proof of Michael's theorem to generate approximations to the target selection. The second is used in the iterative step to generate new lower hemicontinuous maps.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
139/0 |
Mathlib/Topology/Semicontinuity/Defs.lean |
1 |
8 |
['eric-wieser', 'github-actions', 'j-loreaux', 'khwilson'] |
j-loreaux assignee:j-loreaux |
3-3738 3 days ago |
3-83348 3 days ago |
10-58002 10 days |
| 39011 |
Vierkantor author:Vierkantor |
chore(Algebra/Polynomial/Module): workaround for backward.inferInstanceAs |
This PR, like #38990, works around a `backward.inferInstanceAs` compatibility flag introduced by identifying `PolynomialModule` with `Finsupp` in our definitions. We introduce a new dsimp lemma `funLike_eq` that transfers the `FunLike` instances, and now we can use `PolynomialModule`'s `FunLike` instance, instead of the custom `CoeFun` instance.
This is not a great approach, but it seems the least painful for the short term. The alternative would be to strictly enforce the defeq barrier between `PolynomialModule` and `Finsupp`, which would mean a substantial rewrite of this corner of Mathlib. We can't make `PolynomialModule` an `@[implicit_reducible]`, because we need different multiplication on it than `Finsupp` has.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
tech debt
label:t-algebra$ |
8/5 |
Mathlib/Algebra/Polynomial/Module/Basic.lean |
1 |
1 |
['github-actions'] |
nobody |
3-2540 3 days ago |
23-30604 23 days ago |
23-30373 23 days |
| 37062 |
tannerduve author:tannerduve |
feat(Computability): Turing join and semilattice structure on Turing degrees |
## Summary
- Add `Partrec.kronecker` (equality test) and `Partrec.join` (disjoint union by parity) in `Partrec.lean`
- Prove `Nat.RecursiveIn` is closed under computable conditionals (`cond_const`, `cond`)
- Show each component reduces to the join (`left_le_join`, `right_le_join`) and the join is the least upper bound (`join_le`)
- Establish `SemilatticeSup` instance on `TuringDegree` |
t-computability
new-contributor
large-import
|
311/15 |
Mathlib/Computability/Partrec.lean,Mathlib/Computability/RecursiveIn.lean,Mathlib/Computability/TuringDegree.lean |
3 |
7 |
['Komyyy', 'github-actions', 'mathlib-merge-conflicts', 'tannerduve'] |
Komyyy assignee:Komyyy |
3-2367 3 days ago |
46-37445 46 days ago |
47-13108 47 days |
| 39895 |
yuanyi-350 author:yuanyi-350 |
refactor(Analysis): golf `Mathlib/Analysis/Normed/Module/MStructure` |
- refactors `Normed/Module/MStructure` by replacing a norm-zero argument with `nlinarith` and shortening the proof of `QP_eq_QPQ`
Extracted from #37968
[](https://gitpod.io/from-referrer/) |
codex
t-analysis
LLM-generated
|
6/10 |
Mathlib/Analysis/Normed/Module/MStructure.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
3-2217 3 days ago |
3-3470 3 days ago |
3-3239 3 days |
| 39897 |
yuanyi-350 author:yuanyi-350 |
refactor(Analysis): golf `Mathlib/Analysis/Normed/Ring/Basic` |
- refactors `Normed/Ring/Basic` by removing redundant nonempty-case splits from `Real.iSup_fun_mul_eq_iSup_mul_iSup_of_nonneg`
Extracted from #37968
[](https://gitpod.io/from-referrer/) |
codex
t-analysis
LLM-generated
|
0/4 |
Mathlib/Analysis/Normed/Ring/Basic.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
3-2215 3 days ago |
3-3466 3 days ago |
3-3235 3 days |
| 39894 |
yuanyi-350 author:yuanyi-350 |
refactor(Analysis): golf `Mathlib/Analysis/Normed/Lp/WithLp` |
- refactors `Normed/Lp/WithLp` by deriving scalar tower and scalar commutation instances from `WithLp.equiv`
Extracted from #37968
[](https://gitpod.io/from-referrer/) |
codex
t-analysis
LLM-generated
|
4/8 |
Mathlib/Analysis/Normed/Lp/WithLp.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
3-1965 3 days ago |
3-3472 3 days ago |
3-3241 3 days |
| 39896 |
yuanyi-350 author:yuanyi-350 |
refactor(Analysis): golf `Mathlib/Analysis/Normed/Operator/ContinuousLinearMap` |
- refactors `Normed/Operator/ContinuousLinearMap` by reusing `mkContinuous` in bounded linear continuity proofs and shortening `homothety_inverse`
Extracted from #37968
[](https://gitpod.io/from-referrer/) |
codex
t-analysis
LLM-generated
|
5/16 |
Mathlib/Analysis/Normed/Operator/ContinuousLinearMap.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
3-1890 3 days ago |
3-3468 3 days ago |
3-3237 3 days |
| 39898 |
yuanyi-350 author:yuanyi-350 |
refactor(Analysis): golf `Mathlib/Analysis/Normed/Unbundled/AlgebraNorm` |
- refactors `Normed/Unbundled/AlgebraNorm` by using structure inheritance in `MulRingNorm.toRingNorm`
Extracted from #37968
[](https://gitpod.io/from-referrer/) |
codex
t-analysis
LLM-generated
|
1/5 |
Mathlib/Analysis/Normed/Unbundled/AlgebraNorm.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
3-1651 3 days ago |
3-3464 3 days ago |
3-3233 3 days |
| 39899 |
yuanyi-350 author:yuanyi-350 |
refactor(Analysis): golf `Mathlib/Analysis/Normed/Unbundled/FiniteExtension` |
- refactors `Normed/Unbundled/FiniteExtension` by proving `Basis.norm_smul` via `Finset.mul₀_sup'`
Extracted from #37968
[](https://gitpod.io/from-referrer/) |
codex
t-analysis
LLM-generated
|
4/15 |
Mathlib/Analysis/Normed/Unbundled/FiniteExtension.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
3-1511 3 days ago |
3-3462 3 days ago |
3-3231 3 days |
| 39900 |
yuanyi-350 author:yuanyi-350 |
refactor(Analysis): golf `Mathlib/Analysis/SpecialFunctions/Gaussian/GaussianIntegral` |
- refactors `Gaussian/GaussianIntegral` by proving `integral_gaussian_complex_Ioi` using `integral_comp_neg_Ioi`
Extracted from #37968
[](https://gitpod.io/from-referrer/) |
codex
t-analysis
LLM-generated
|
13/20 |
Mathlib/Analysis/SpecialFunctions/Gaussian/GaussianIntegral.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
3-1408 3 days ago |
3-3460 3 days ago |
3-3229 3 days |
| 38582 |
dennj author:dennj |
feat(LinearAlgebra/Matrix): add Hadamard matrices |
Introduce `Matrix.IsHadamard` over a general `Ring R`, with the basic theory:
- `IsHadamard` and `IsComplexHadamard` predicates (Definitions 2.3.1 and 2.7.1
of de Launey–Flannery, *Algebraic Design Theory*).
- `IsHadamard.det_sq`: the Hadamard determinant identity `(det A)² = n^n`.
- `IsHadamard.det_ne_zero`: over an integral domain of characteristic zero.
- `IsHadamard.transpose`: `Aᵀ` is Hadamard whenever `A` is (Theorem 2.3.6),
proved over `[CommRing R] [IsDomain R] [CharZero R]` via the adjugate.
- `IsHadamard.card_eq_sq_of_const_row_sum`: a Hadamard matrix with constant
row sum `s` has order `s²` (slightly stronger than Theorem 2.3.7: the
constant-column-sum hypothesis is implied by orthogonality).
- `IsHadamard.kronecker`: the Sylvester (Kronecker product) construction.
- `IsHadamard.four_dvd_card`: order of a Hadamard matrix of order > 2 is
divisible by 4.
`Matrix.mul_eq_smul_one_symm`: if `M * N = c • 1` and `det M ≠ 0` over an
integral domain, then `N * M = c • 1`. Used here for the transpose proof, but
generally useful, analogous to how `mul_eq_one_comm` works over stably finite
rings, but covers the integral-domain case (e.g. `ℤ`, `ℤ[X]`) where matrix
inverses don't exist.
## References
Adds the de Launey–Flannery bibliography entry, cited from the new file.
Human-made PR with LLM used for proof golfing and documentation |
t-algebra
new-contributor
label:t-algebra$ |
270/0 |
Mathlib.lean,Mathlib/Algebra/Group/Action/Defs.lean,Mathlib/Algebra/Group/Commute/Defs.lean,Mathlib/Algebra/Star/Unitary.lean,Mathlib/LinearAlgebra/Matrix/HadamardMatrix.lean,docs/references.bib |
6 |
56 |
['JJYYY-JJY', 'dennj', 'eric-wieser', 'github-actions', 'themathqueen', 'wwylele'] |
themathqueen assignee:themathqueen |
3-915 3 days ago |
17-12967 17 days ago |
32-31776 32 days |
| 38881 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Function/StronglyMeasurable/Basic` |
- shortens `stronglyMeasurable_in_set` by inlining the restricted approximation sequence and folding the `hg_eq` / `hg_zero` helper lemmas into the two `by_cases` branches
Extracted from #38104
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
t-measure-probability
|
7/13 |
Mathlib/MeasureTheory/Function/StronglyMeasurable/Basic.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
RemyDegenne assignee:RemyDegenne |
3-912 3 days ago |
26-42757 26 days ago |
26-42526 26 days |
| 39391 |
emlis42 author:emlis42 |
feat(MeasureTheory/Integral): add integral_congr_uIoo |
This PR adds some congruence lemmas for interval integrals under `NoAtoms μ` and golfs some lemmas.
| Lemma | Heartbeats | Proof Elaboration Time |
---- | ---- | ----
`LocallyIntegrable.ae_hasDerivAt_integral` | 7684 → 5235 (−2449, 31%) | 603ms → 445ms (−157ms, 26%)
`MonotoneOn.exists_tendsto_deriv_liminf_lintegral_enorm_le` | 31019 → 8388 (−22631, 73%) | 2475ms → 631ms (−1843ms, 74%)
`MonotoneOn.intervalIntegral_deriv_mem_uIcc` | 22680 → 5983 (−16697, 73%) | 1713ms → 537ms (−1175ms, 68%)
`AbsolutelyContinuousOnInterval.integral_deriv_mul_eq_sub` | 1475 → 845 (−630, 42%) | 92ms → 41ms (−50ms, 55%)
`fourierCoeff_liftIco_eq` | 1040 → 703 (−337, 32%) | 55ms → 41ms (−13ms, 24%)
`taylor_integral_remainder_aux` | 26585 → 18827 (−7758, 29%) | 2095ms → 1575ms (−520ms, 24%)
Profiled on top of commit `9e407aa1ef1be515a1bd0e1c1fc081d5b855f25e` using `set_option trace.profiler true in` and
```
set_option Elab.async false in
#count_heartbeats in
```
|
t-measure-probability
new-contributor
|
52/35 |
Mathlib/Analysis/Calculus/Taylor.lean,Mathlib/Analysis/Fourier/AddCircle.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/AbsolutelyContinuousFun.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/Basic.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/DerivIntegrable.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/LebesgueDifferentiationThm.lean |
6 |
3 |
['github-actions', 'mathlib-merge-conflicts'] |
kex-y assignee:kex-y |
3-911 3 days ago |
4-36547 4 days ago |
13-28739 13 days |
| 39910 |
justus-springer author:justus-springer |
feat(AlgebraicGeometry/Morphisms/UniversallyInjective): equivalent criteria for universally injective morphisms |
We prove [stacks 01S4](https://stacks.math.columbia.edu/tag/01S4), which gives two new equivalent criteria for being universally injective.
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-geometry
large-import
|
99/6 |
Mathlib/AlgebraicGeometry/Morphisms/UniversallyInjective.lean,Mathlib/AlgebraicGeometry/ResidueField.lean |
2 |
2 |
['github-actions', 'justus-springer'] |
nobody |
2-61654 2 days ago |
2-61732 2 days ago |
2-61501 2 days |
| 31222 |
Thmoas-Guan author:Thmoas-Guan |
feat(Algebra): `Hom` commute with flat base change |
In this PR, we proved `Hom_S (M \tensor S, N \tensor S)` is base change of `Hom_R (M, N)` with respect to `LinearMap.baseChangeHom`.
Co-authored-by: Wang Jingting
---
- [x] depends on: #31218
- [x] depends on: #31219
- [x] depends on: #31696
[](https://gitpod.io/from-referrer/)
|
large-import
t-algebra
label:t-algebra$ |
49/0 |
Mathlib/Algebra/Module/FinitePresentation.lean |
1 |
5 |
['github-actions', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot'] |
kim-em assignee:kim-em |
2-56809 2 days ago |
29-11102 29 days ago |
29-11137 29 days |
| 39185 |
ooovi author:ooovi |
feat(Geometry/Convex/Cone/Pointed): faces of pointed cones |
- Define PointedCone.IsFaceOf, for a pointed cone being a face of another pointed cone.
- Prove some basic properties, that faces are extreme sets of their cone, and how they behave under intersection, map and product operations.
Co-authored-by: Martin Winter
---
split off of #33664
[](https://gitpod.io/from-referrer/)
|
t-convex-geometry |
289/0 |
Mathlib.lean,Mathlib/Geometry/Convex/Cone/Face/Basic.lean |
2 |
4 |
['YaelDillies', 'github-actions', 'martinwintermath', 'mathlib-bors'] |
YaelDillies assignee:YaelDillies |
2-53950 2 days ago |
2-53950 2 days ago |
2-56378 2 days |
| 39886 |
grunweg author:grunweg |
chore(Geometry/Manifold): remove some `@[expose] public` section |
Go through a few files and audit the exposed definitions there. Best reviewed commit by commit.
---
I'm happy to give more details on any file where desired.
[](https://gitpod.io/from-referrer/)
|
t-differential-geometry
tech debt
|
17/20 |
Mathlib/Geometry/Manifold/Bordism.lean,Mathlib/Geometry/Manifold/VectorField/LieBracket.lean,Mathlib/Geometry/Manifold/WhitneyEmbedding.lean |
3 |
1 |
['github-actions'] |
JovanGerb assignee:JovanGerb |
2-53539 2 days ago |
3-19132 3 days ago |
3-18901 3 days |
| 39067 |
mbkybky author:mbkybky |
feat(Algebra/Module): define modules admitting finite free resolutions |
We say that an `R`-module `M` has a finite free resolution if there exists an exact sequence `0 ⟶ Eₙ ⟶ ⋯ ⟶ E₀ ⟶ M ⟶ 0` such that `Eᵢ` are finite free `R`-modules.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
186/0 |
Mathlib.lean,Mathlib/Algebra/Module/Equiv/Defs.lean,Mathlib/Algebra/Module/FiniteFreeResolution/Basic.lean |
3 |
1 |
['github-actions'] |
nobody |
2-53253 2 days ago |
18-35229 18 days ago |
21-57991 21 days |
| 39369 |
pd4st8hb95-hub author:pd4st8hb95-hub |
feat: add basic fuzzy set definitions |
This PR adds a minimal `FuzzySet` API in `Mathlib/Order/FuzzySet`.
A fuzzy set is represented as an abbreviation:
`FuzzySet α L := α → L`
The file provides basic definitions and lemmas:
- `degree`
- `support`
- `core`
- `weakCut`
- `strongCut`
- membership simp lemmas
- extensionality
- basic monotonicity lemmas for weak and strong cuts
This PR intentionally does not add complement, union/intersection-specific API, normal or convex fuzzy sets, fuzzy relations, or advanced fuzzy set theory.
Validation:
- `lake build Mathlib.Order.FuzzySet`
- `#lint only docBlame docBlameThm`
Feedback on whether `Mathlib/Order/FuzzySet.lean` is the right location for this minimal API would be appreciated.
---
[](https://gitpod.io/from-referrer/)
|
t-order
new-contributor
|
169/0 |
Mathlib.lean,Mathlib/Order/FuzzySet.lean |
2 |
6 |
['github-actions', 'grunweg', 'pd4st8hb95-hub', 'wwylele'] |
nobody |
2-45072 2 days ago |
13-42673 13 days ago |
13-42802 13 days |
| 39307 |
FordUniver author:FordUniver |
feat(Combinatorics/SimpleGraph/Copy): introduce `UnlabeledCopy` carrier subtype |
Adds `abbrev UnlabeledCopy A B := {B' : B.Subgraph // Nonempty (A ≃g B'.coe)}` and uses it to replace the previous inline filter-set body of `copyCount G H`. Drops the now unused legacy Finset-image bridge `copyCount_eq_card_image_copyToSubgraph`. Adds `uniqueUnlabeledCopyBot` instance so `copyCount_bot` is a one-liner via `Fintype.card_unique`.
Co-authored-by: Malte Jackisch <45597826+MaltyBlanket@users.noreply.github.com>
---
**Step 1/5 of the `Copy` / `InducedCopy` refactor-feat stack.**
This PR isolates the `UnlabeledCopy` type introduction and the count's type-form redefinition from the larger rename/convention work in the rest of the stack. Note that resolving the current clash in naming (`Copy` and `UnlabeledCopy` vs `labelledCopyCount` and `copyCount`) is part of #38745.
|
t-combinatorics
maintainer-merge
|
32/30 |
Mathlib/Combinatorics/SimpleGraph/Copy.lean |
1 |
8 |
['FordUniver', 'YaelDillies', 'github-actions', 'mathlib-bors', 'mathlib-merge-conflicts', 'mitchell-horner'] |
nobody |
2-40703 2 days ago |
4-67067 4 days ago |
14-75975 14 days |
| 39288 |
FordUniver author:FordUniver |
feat(Combinatorics/SimpleGraph/Subgraph): add `Embedding.ofIsInduced` and `IsInduced.map` |
Three additions to the `SimpleGraph.Subgraph` API for induced subgraphs. `Embedding.ofIsInduced` is the canonical embedding of an induced subgraph into its ambient graph, paired with `toHom_ofIsInduced` and `ofIsInduced_apply` lemmas. This is the embedding counterpart of `Subgraph.hom`, which only produces a homomorphism because non-induced subgraphs do not reflect adjacency. `Subgraph.IsInduced.map` then records that the image of an induced subgraph under a graph embedding is induced, strengthened to `IsInduced.map_iff` for the iso case.
Co-authored-by: Malte Jackisch <45597826+MaltyBlanket@users.noreply.github.com>
---
**Orthogonal pre-requisite of the `Copy` / `InducedCopy` refactor-feat stack.**
Extracted as a prerequisite from #38631 that is otherwise independent of the wider `Copy` / `InducedCopy` refactor-feat stack. |
t-combinatorics |
27/4 |
Mathlib/Combinatorics/SimpleGraph/Copy.lean,Mathlib/Combinatorics/SimpleGraph/Subgraph.lean |
2 |
16 |
['FordUniver', 'SnirBroshi', 'github-actions', 'mathlib-bors', 'mathlib-merge-conflicts'] |
nobody |
2-40167 2 days ago |
4-66683 4 days ago |
16-15968 16 days |
| 39691 |
Raph-DG author:Raph-DG |
feat(Topology): An open cover of a preconnected set has no isolated components |
In this PR we show that a family of open sets whose union is preconnected has the property that for any two (nonempty) sets U and V in the cover there is a sequence of sets in the cover U = U_0, U_1,..., U_n = V such that U_i \cap U_{i+1} is nonempty for all i.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
20/0 |
Mathlib/Topology/Connected/Basic.lean |
1 |
5 |
['Raph-DG', 'github-actions', 'plp127'] |
nobody |
2-39566 2 days ago |
6-49843 6 days ago |
7-56223 7 days |
| 39690 |
b-mehta author:b-mehta |
feat(Analysis/Complex/Exponential): add new bounds on exponential |
We add new upper bounds on Real.exp in terms of 2x/(2+x), and use these to move some bounds on log higher in mathlib.
We also add a lemma for the common bound (1+1/n)^n <= e, though this is a special-case of `one_sub_div_pow_le_exp_neg` (immediately before), but is added for convenience and discoverability, as this is a "well-known" bound.
---
[](https://gitpod.io/from-referrer/)
|
t-analysis |
36/11 |
Mathlib/Analysis/Complex/Exponential.lean,Mathlib/Analysis/Complex/ExponentialBounds.lean,Mathlib/Analysis/SpecialFunctions/Log/Basic.lean,Mathlib/Analysis/SpecialFunctions/Log/Deriv.lean |
4 |
3 |
['github-actions', 'mathlib-merge-conflicts'] |
nobody |
2-38468 2 days ago |
2-38507 2 days ago |
6-8182 6 days |
| 39935 |
FordUniver author:FordUniver |
feat(Combinatorics/SimpleGraph/Finite): LocallyFiniteOrder |
Adds an order-theoretic `LocallyFiniteOrder (SimpleGraph V)` instance (closed intervals are finite), distinct from the existing graph-theoretic `LocallyFinite` (vertex degrees) already in this file. The instance takes `DecidableLE` as an explicit hypothesis rather than routing through `Classical`, because per-graph `DecidableRel G.Adj` is value-dependent and cannot be a free global instance.
Co-authored-by: Malte Jackisch <45597826+MaltyBlanket@users.noreply.github.com>
---
Came up while writing a Möbius inversion between copy counts and induced copy counts ([WIP](https://github.com/FordUniver/mathlib4/pull/36/changes)) that sums over the closed interval `Finset.Icc G ⊤` of supergraphs. Decidability of the order plus local-finiteness of the lattice felt like a clean standalone piece to land first, before the rest of the Möbius file.
Less sure about what the conventions for declaring type class instances are in mathlib, let me know if this is not of the expected shape or should not be included at all. |
t-combinatorics |
20/0 |
Mathlib/Combinatorics/SimpleGraph/Finite.lean |
1 |
1 |
['github-actions'] |
nobody |
2-35583 2 days ago |
2-36928 2 days ago |
2-36697 2 days |
| 39907 |
Hagb author:Hagb |
feat(Order/InititalSeg): `PrincipalSeg` is trichotomous for well orders |
For any two well orders, one is a principal segment of the other, or they are isomorphic.
Suggested by @vihdzp in the review of #39545
https://github.com/leanprover-community/mathlib4/pull/39545#discussion_r3262466782. It may slightly simplify the proof of `infinite_iff_nonempty_relEmbedding_of_isWellOrder`.
---
[](https://gitpod.io/from-referrer/)
|
t-order |
7/0 |
Mathlib/Order/InitialSeg.lean |
1 |
1 |
['github-actions', 'vihdzp'] |
nobody |
2-33595 2 days ago |
2-75905 2 days ago |
2-75674 2 days |
| 39905 |
plp127 author:plp127 |
chore(Order/CompleteBooleanAlgebra): dualize `symmDiff` theorems |
Dualize some `symmDiff` theorems, and also generalize them from `CompleteBooleanAlgebra` to `Order.Coframe`.
---
[](https://gitpod.io/from-referrer/)
|
t-order |
76/39 |
Mathlib/Order/CompleteBooleanAlgebra.lean |
1 |
3 |
['github-actions', 'plp127', 'vihdzp'] |
nobody |
2-32542 2 days ago |
3-1506 3 days ago |
3-1275 3 days |
| 37073 |
kim-em author:kim-em |
feat: add wrap_instance% using core's wrapInstance |
This PR adds a new `wrap_instance%` term elaborator that delegates to Lean core's
`wrapInstance` (from https://github.com/leanprover/lean4/pull/12897), and replaces ~53
`fast_instance%` call sites where the replacement is safe.
`wrap_instance%` is a thin wrapper (~15 lines) around `Lean.Meta.wrapInstance`. Like
`fast_instance%`, it reduces instances to constructor applications and reuses canonical
sub-instances. Unlike `fast_instance%`, it works at `instances` transparency and delegates all
normalization logic to core.
The replaced sites cover:
- Equiv/type-alias transfers (WithAbs, WithConv, WithVal, WithLp, TransferInstance)
- Surjective constructors (Con, RingCon quotients, module congruences)
- DFunLike leaf instances (MultilinearMap, ContinuousMultilinearMap, AlternatingMap, Intertwining)
- Quotient instances (LinearAlgebra/Quotient/Defs)
- inferInstanceAs% sites (StandardPart, Presentation/Core)
- Miscellaneous (InfiniteAdeleRing, ZMod)
This PR *doesn't* attempt to replace all `fast_instance%`; it gets more complicated!
🤖 Prepared with Claude Code |
|
88/59 |
Mathlib/Algebra/Algebra/TransferInstance.lean,Mathlib/Algebra/Module/Congruence/Defs.lean,Mathlib/Algebra/WithConv.lean,Mathlib/Analysis/Normed/Lp/WithLp.lean,Mathlib/Analysis/Normed/Ring/WithAbs.lean,Mathlib/Data/ZMod/Basic.lean,Mathlib/GroupTheory/Congruence/Defs.lean,Mathlib/LinearAlgebra/Alternating/Basic.lean,Mathlib/LinearAlgebra/Multilinear/Basic.lean,Mathlib/LinearAlgebra/Quotient/Defs.lean,Mathlib/RepresentationTheory/Intertwining.lean,Mathlib/RingTheory/Extension/Presentation/Core.lean,Mathlib/Tactic/FastInstance.lean,Mathlib/Topology/Algebra/Module/Alternating/Basic.lean,Mathlib/Topology/Algebra/Module/Multilinear/Basic.lean,Mathlib/Topology/Algebra/Valued/WithVal.lean |
16 |
8 |
['JovanGerb', 'github-actions', 'kim-em', 'leanprover-radar', 'mathlib-merge-conflicts'] |
nobody |
2-24903 2 days ago |
2-24940 2 days ago |
32-14447 32 days |
| 37071 |
ericluap author:ericluap |
feat: Dedekind completion of rationals is isomorphic to EReal |
|
t-order
new-contributor
|
128/4 |
Mathlib.lean,Mathlib/Data/EReal/Basic.lean,Mathlib/Data/EReal/DedekindCut.lean,Mathlib/Order/Completion.lean |
4 |
59 |
['ericluap', 'github-actions', 'plp127', 'vihdzp', 'wwylele'] |
vihdzp assignee:vihdzp |
2-23215 2 days ago |
18-34373 18 days ago |
41-29330 41 days |
| 39724 |
vihdzp author:vihdzp |
feat: finite sets are closed under directed suprema |
As are chains of length ≤ ω.
---
We don't prove `Set.Finite.dirSupClosed` via `DirectedOn.finite_le`, in order to save a few imports.
[](https://gitpod.io/from-referrer/)
|
file-removed
t-order
|
239/31 |
Mathlib.lean,Mathlib/Data/Fintype/Order.lean,Mathlib/Order/Cofinal.lean,Mathlib/Order/DirSupClosed/Basic.lean,Mathlib/Order/DirSupClosed/Finite.lean,Mathlib/Order/IsNormal.lean,Mathlib/SetTheory/Cardinal/Cofinality/Club.lean,Mathlib/SetTheory/Cardinal/Cofinality/Ordinal.lean,Mathlib/Topology/Order/ScottTopology.lean |
9 |
2 |
['github-actions', 'mathlib-merge-conflicts'] |
nobody |
2-22153 2 days ago |
2-22190 2 days ago |
5-41944 5 days |
| 35217 |
kim-em author:kim-em |
feat: auxiliary lemmas for Artin and braid groups |
This PR adds small lemmas to existing files, in preparation for the Artin groups and braid groups PRs.
- `Commute.mul_pow_eq_one`: for commuting elements with `a ^ m = 1` and `b ^ m = 1`
- `Equiv.Perm.swap_conjugate`: braid relation for adjacent transpositions
- `Equiv.Perm.swap_mul_swap_comm_of_disjoint`: disjoint transpositions commute
- `@[grind =]` attributes on `Perm.mul_apply`, `Perm.one_apply`; new `Perm.pow_add_one_apply`
- `Subgroup.normalClosure_singleton_one`
- `FreeGroup.ofList` and associated lemmas
- `FreeGroup.freeGroupUnitMulEquivInt`
- `PresentedGroup.instUniqueOfIsEmpty`
- `CoxeterMatrix.Aₙ_adjacent`, `CoxeterMatrix.Aₙ_far`
🤖 Prepared with Claude Code |
t-group-theory
LLM-generated
|
98/2 |
Mathlib/Algebra/Group/Commute/Defs.lean,Mathlib/Algebra/Group/End.lean,Mathlib/Algebra/Group/Subgroup/Basic.lean,Mathlib/GroupTheory/Coxeter/Matrix.lean,Mathlib/GroupTheory/FreeGroup/Basic.lean,Mathlib/GroupTheory/Perm/Cycle/Basic.lean,Mathlib/GroupTheory/PresentedGroup.lean |
7 |
17 |
['eric-wieser', 'github-actions', 'kim-em', 'mathlib-merge-conflicts', 'themathqueen'] |
thorimur assignee:thorimur |
2-21945 2 days ago |
2-21857 2 days ago |
23-14857 23 days |
| 39533 |
b-mehta author:b-mehta |
feat(Data/Finset/Image): add image_comp and image_comp_image |
The statement `image_comp` is worth adding because it matches the Set version, and also is more useful for rewriting in the forward direction.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
13/0 |
Mathlib/Data/Finset/Image.lean,Mathlib/Data/Set/Image.lean |
2 |
5 |
['b-mehta', 'github-actions', 'j-loreaux', 'themathqueen'] |
nobody |
2-19647 2 days ago |
4-27915 4 days ago |
5-33821 5 days |
| 39759 |
plp127 author:plp127 |
chore(FieldTheory/KrullTopology): move lemmas to earlier file |
We move some lemmas unrelated to the Krull topology out of the `KrullTopology` file. They are placed in the earlier file `FieldTheory/IsGalois/Basic` instead.
---
In #23693 it is said that
> The proof of it uses some results in this file, so it can't be put into earlier files.
This is no longer true, so we want move it out of the `KrullTopology` file because the theorems have nothing to do with the Krull topology. I found that they can go in `FieldTheory/IsGalois/Basic` without modifying the proofs. They cannot go any earlier because the statement of the theorems contains `IsGalois`, which is defined in this file.
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
59/68 |
Mathlib/FieldTheory/Galois/Basic.lean,Mathlib/FieldTheory/KrullTopology.lean |
2 |
5 |
['acmepjz', 'github-actions', 'grunweg', 'plp127', 'vihdzp'] |
nobody |
2-19587 2 days ago |
6-16436 6 days ago |
6-16205 6 days |
| 39865 |
eliasjudin author:eliasjudin |
feat(Algebra): add eval API parity lemmas |
Adds two eval API parity lemmas from #23044: `MvPolynomial.hom_eval₂`, parallel to `Polynomial.hom_eval₂`, and `Polynomial.eval₂RingHom_comp_C`, parallel to `MvPolynomial.eval₂Hom_comp_C`.
This addresses the eval portion of #23044; the degree-name discussion there is left for separate work.
|
t-algebra
new-contributor
label:t-algebra$ |
10/0 |
Mathlib/Algebra/MvPolynomial/Eval.lean,Mathlib/Algebra/Polynomial/Eval/Defs.lean |
2 |
2 |
['github-actions'] |
nobody |
2-18285 2 days ago |
3-61992 3 days ago |
3-61761 3 days |
| 37870 |
Jun2M author:Jun2M |
feat(Combinatorics/Graph): `Simple` typeclass for `Graph` |
This PR introduces two type classes on `Graph`: `Loopless` and `Simple`.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
92/0 |
Mathlib.lean,Mathlib/Combinatorics/Graph/Simple.lean |
2 |
8 |
['Jun2M', 'YaelDillies', 'github-actions', 'mathlib-merge-conflicts'] |
YaelDillies assignee:YaelDillies |
2-18024 2 days ago |
28-85854 28 days ago |
48-33656 48 days |
| 39811 |
TheGoedeDoel author:TheGoedeDoel |
feat(CategoryTheory): functors of submonoids |
We add a definition of a functor of submonoids: For a functor `M : C ⥤ MonCat`, a submonoid functor consists of a submonoid of `M.obj U` for every `U`, compatible with the restriction maps `M.map i`. We provide the complete lattice structure on `SubmonoidFunctor M` and a map and comap operation.
In a follow-up PR, we will use this to define the localisation of a presheaf of modules along a submonoid functor of the sheaf of rings.
See also https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Subfunctors.20with.20algebraic.20structure/with/587726088 for a discussion of alternative designs.
---
[](https://gitpod.io/from-referrer/)
|
t-category-theory
new-contributor
maintainer-merge
|
183/2 |
Mathlib.lean,Mathlib/Algebra/Group/Submonoid/Operations.lean,Mathlib/CategoryTheory/Subfunctor/SubmonoidFunctor.lean |
3 |
110 |
['TheGoedeDoel', 'chrisflav', 'github-actions', 'joelriou', 'quantumsnow'] |
chrisflav assignee:chrisflav |
2-16014 2 days ago |
3-26689 3 days ago |
3-43438 3 days |
| 39802 |
vihdzp author:vihdzp |
feat: more theorems on `toBoolRing` |
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
23/0 |
Mathlib/Algebra/Ring/BooleanRing.lean |
1 |
3 |
['github-actions', 'plp127'] |
nobody |
2-14889 2 days ago |
2-15024 2 days ago |
3-55743 3 days |
| 39727 |
vihdzp author:vihdzp |
feat: stationary sets |
We define stationary sets as sets intersecting all club sets, and prove basic theorems about them.
---
[](https://gitpod.io/from-referrer/)
|
t-set-theory
maintainer-merge
|
154/22 |
Mathlib/Order/Cofinal.lean,Mathlib/SetTheory/Cardinal/Cofinality/Club.lean |
2 |
7 |
['YaelDillies', 'github-actions', 'vihdzp'] |
nobody |
2-13929 2 days ago |
5-37875 5 days ago |
7-8600 7 days |
| 39613 |
sharky564 author:sharky564 |
feat(LinearAlgebra/Projection): add quotientEquivOfIsCompl_comp_mkQ and quotientEquivOfIsTopCompl_comp_mkQ |
Adds the lemmas `Submodule.quotientEquivOfIsCompl_comp_mkQ` and `quotientEquivOfIsTopCompl_comp_mkQ` - the composition of `quotientEquivOfIsCompl`/`quotientEquivOfIsTopCompl` with `mkQ` agrees with the linear projection onto `q` along `p`. Additionally the proof of `IsCompl.isTopCompl_iff_continuous_quotientEquivOfIsCompl` is simplified.
---
This lemma was flagged as missing in the API in the review of #39260 by @themathqueen. Upon review of the lemma, I found it could be further simplified. |
t-algebra
t-topology
label:t-algebra$ |
11/4 |
Mathlib/LinearAlgebra/Projection.lean,Mathlib/Topology/Algebra/Module/Complement.lean |
2 |
9 |
['ADedecker', 'github-actions', 'sharky564', 'themathqueen'] |
nobody |
2-4925 2 days ago |
5-82938 5 days ago |
9-2054 9 days |
| 38231 |
NoneMore author:NoneMore |
feat(ModelTheory/Definablity): add syntax-to-definability bridge lemmas |
Add bridge lemmas from syntax to definability and refactor downstream proofs to use them.
---
[](https://gitpod.io/from-referrer/) |
t-logic |
88/56 |
Mathlib/ModelTheory/Definability.lean,Mathlib/ModelTheory/ElementarySubstructures.lean |
2 |
1 |
['github-actions'] |
nobody |
2-2544 2 days ago |
40-73628 40 days ago |
40-73397 40 days |
| 38815 |
dagurtomas author:dagurtomas |
feat(Tactic/CategoryTheory): extend `@[to_app]` to natural transformations |
This extends the `@[to_app]` attribute so it also generates componentwise lemmas from equalities of natural transformations between functors, while preserving the existing bicategory behavior. It also ensures generated component lemmas remain usable by dsimp when they are definitionally true. |
t-category-theory
LLM-generated
t-meta
|
148/22 |
Mathlib/Tactic/CategoryTheory/ToApp.lean,Mathlib/Util/AddRelatedDecl.lean,MathlibTest/CategoryTheory/ToApp.lean |
3 |
1 |
['github-actions'] |
nobody |
2-2540 2 days ago |
28-28043 28 days ago |
28-27866 28 days |
| 39495 |
hawkrobe author:hawkrobe |
feat(Data/Multiset/Antidiagonal): two structural lemmas |
Adds `map_swap_antidiagonal` and `antidiagonal_add`.
---
Fills out the API parallel to `Multiset.Nat.map_swap_antidiagonal` and `Finset.map_swap_antidiagonal`. (And adds `@[congr]` to `bind_congr`.)
Used downstream for shuffle-coproduct constructions.
(#7486, I found this old [Zulip thread](https://leanprover.zulipchat.com/#narrow/channel/144837-PR-reviews/topic/antidiagonals.20having.20multiplicity.20.237595/near/238573473))
I used Claude Code to audit and polish. |
t-data
new-contributor
|
20/0 |
Mathlib/Data/Multiset/Antidiagonal.lean,Mathlib/Data/Multiset/Bind.lean |
2 |
6 |
['github-actions', 'hawkrobe', 'j-loreaux'] |
nobody |
2-2090 2 days ago |
9-46527 9 days ago |
12-27288 12 days |
| 32282 |
jsm28 author:jsm28 |
feat(Geometry/Euclidean/Angle/Incenter): unoriented angle bisection |
Add lemmas giving unoriented angles involving the incenter and excenters of a triangle as expressions involving dividing angles of the triangle by 2, deduced from oriented bisection lemmas.
---
- [ ] depends on: #30981
- [ ] depends on: #30982
- [ ] depends on: #31205
- [ ] depends on: #32019
- [ ] depends on: #32021
- [ ] depends on: #32259
- [ ] depends on: #32260
- [ ] depends on: #32270
- [ ] depends on: #32273
- [ ] depends on: #32278
[](https://gitpod.io/from-referrer/)
|
t-euclidean-geometry |
98/0 |
Mathlib/Geometry/Euclidean/Angle/Incenter.lean |
1 |
8 |
['github-actions', 'jsm28', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot', 'wwylele'] |
eric-wieser assignee:eric-wieser |
2-1402 2 days ago |
63-26496 63 days ago |
63-27001 63 days |
| 35868 |
Raph-DG author:Raph-DG |
feat(Topology): add variant of the sheaf condition which assumes non triviality of the cover |
In this PR we add in a variant of the sheaf condition which assumes the cover present in the sheaf condition is nontrivial in the sense that the indexing type is nonempty and the values of the presheaf on each element of the cover are nonempty.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
54/0 |
Mathlib/Topology/Sheaves/SheafCondition/UniqueGluing.lean |
1 |
5 |
['Raph-DG', 'chrisflav', 'github-actions'] |
alreadydone assignee:alreadydone |
2-1400 2 days ago |
28-61518 28 days ago |
34-38753 34 days |
| 37714 |
mortarsanjaya author:mortarsanjaya |
feat(Algebra/Order/Floor/Defs): `Nat.cast` is strictly monotone in `FloorSemiring` and `FloorRing` |
As title says, and without the `IsOrderedRing` assumption.
Other than that, I removed the `IsOrderedRing` assumption from pretty much all the lemmas in `Algebra/Order/Floor/Defs` that could possibly have this assumption removed, and reduced some `IsStrictOrderedRing` assumptions to `IsOrderedRing` + `Nontrivial`.
Due to strict monotonicity, we can also provide `CharZero` instance on `FloorSemiring` and `FloorRing`. Thus we can remove the `NeZero` and `Nontrivial` instances on them.
The changes on `/Ring` and `/Semiring` are trivial changes due to some lemmas not requiring an `IsOrderedRing` instance anymore.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
96/39 |
Mathlib/Algebra/ContinuedFractions/Computation/Approximations.lean,Mathlib/Algebra/ContinuedFractions/Computation/TerminatesIffRat.lean,Mathlib/Algebra/Order/Floor/Defs.lean,Mathlib/Algebra/Order/Floor/Ring.lean,Mathlib/Algebra/Order/Floor/Semiring.lean |
5 |
24 |
['dagurtomas', 'eric-wieser', 'github-actions', 'mathlib-bors', 'mortarsanjaya'] |
riccardobrasca assignee:riccardobrasca |
2-1394 2 days ago |
28-48314 28 days ago |
52-47573 52 days |
| 38049 |
WilliamCoram author:WilliamCoram |
feat: lemmas towards showing gaussNorm on MvPowerSeries is an absolute value |
We prove lemmas: ``gaussNorm_mul_le`` and ``gaussNorm_le_mul`` which will allow us to show it is an absolute value on Mv restricted power series.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
new-contributor
|
144/1 |
Mathlib/RingTheory/MvPowerSeries/GaussNorm.lean |
1 |
4 |
['WilliamCoram', 'github-actions'] |
riccardobrasca assignee:riccardobrasca |
2-1392 2 days ago |
45-31183 45 days ago |
45-30952 45 days |
| 38432 |
SnirBroshi author:SnirBroshi |
feat(Logic/Relation): `Map r f g ≤ s ↔ r ≤ s.bicompl f g` |
and the dual `s ≤ Relation.Map r f g ↔ s.bicompl f g ≤ r` which requires `f` and `g` to be bijective.
Adds `Galois{Connection/Insertion/Coinsertion}` for the dual.
The theorems are specialized to `onFun` instead of `bicompl` for when `f = g`.
The `≤` theorems are spelled using `Subrelation` since `≤` is not yet available in this file, and `∀` for the `bicompl` theorems since `Subrelation` only supports homogeneous relations.
A `GaloisConnection` for the iff in the title requires `f`/`g` to be bijective, but then we can get an `OrderIso` which is stronger (see #38499).
---
[](https://gitpod.io/from-referrer/)
|
t-logic |
119/28 |
Mathlib/Logic/Relation.lean,Mathlib/Order/GaloisConnection/Basic.lean |
2 |
3 |
['SnirBroshi', 'github-actions', 'plp127'] |
fpvandoorn assignee:fpvandoorn |
2-1390 2 days ago |
34-75055 34 days ago |
36-9846 36 days |
| 38875 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Covering/Besicovitch` |
- shortens the proof of `r_t0` in `exists_closedBall_covering_tsum_measure_le` by turning the contradiction argument into a direct lambda
- replaces the manual `simp only` proof with `mem_iUnion₂` and a final `simp [r, this]`
Extracted from #38104
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
t-measure-probability
|
3/8 |
Mathlib/MeasureTheory/Covering/Besicovitch.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
kex-y assignee:kex-y |
2-1389 2 days ago |
26-45149 26 days ago |
26-44918 26 days |
| 38883 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Function/AEMeasurableSequence` |
- rewrites `iSup` by filtering directly along `aeSeq_eq_fun_ae hf hp`, instead of proving a subset statement about `aeSeqSet` and then using `measure_mono_null`
Extracted from #38104
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
t-measure-probability
|
2/6 |
Mathlib/MeasureTheory/Function/AEMeasurableSequence.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
RemyDegenne assignee:RemyDegenne |
2-1387 2 days ago |
26-42319 26 days ago |
26-42088 26 days |
| 39294 |
Sfgangloff author:Sfgangloff |
feat(SymbolicDynamics): prove LanguageOn monotonicity under intersection |
In symbolic dynamics.
This PR proves that taking the language over a finite shape is monotone with respect to intersections of configuration sets:
```math
\mathrm{LanguageOn}(X \cap Y)\, U
\subseteq
\mathrm{LanguageOn}\, X\, U \cap \mathrm{LanguageOn}\, Y\, U
```
The proof is a direct unfolding of definitions: a pattern in the language of `X ∩ Y` comes from restricting a configuration `x ∈ X ∩ Y`. Since such an `x` belongs simultaneously to `X` and `Y`, the same restriction witness gives membership both in `LanguageOn X U` and in `LanguageOn Y U`, yielding membership in their intersection.
Related to issue #39252 |
t-dynamics
new-contributor
|
9/1 |
Mathlib/Dynamics/SymbolicDynamics/Basic.lean |
1 |
2 |
['github-actions'] |
ADedecker assignee:ADedecker |
2-1386 2 days ago |
16-56432 16 days ago |
16-56201 16 days |
| 39411 |
JovanGerb author:JovanGerb |
feat(Push): allow pushing `∀` through `∃` |
This PR adds `Classical.skolem` to the `push` set. This allows pusing a forall through an exists, which can sometimes be convenient.
This PR also removes `forall_self_imp` from the `push` set. I'm not sure why I added it in the first place - I think it is out of scope.
This PR also fixes a subtle bug in `push` which causes `push` to not be idempotent. Namely that the default value of `post` returns `.done` instead of `.continue`, causing the tactic to stop earlier than it should/
---
[](https://gitpod.io/from-referrer/)
|
t-meta |
9/3 |
Mathlib/Tactic/Push.lean,MathlibTest/Tactic/Push/Basic.lean |
2 |
3 |
['github-actions', 'mathlib-merge-conflicts'] |
dwrensha assignee:dwrensha |
2-1385 2 days ago |
7-49515 7 days ago |
0-6372 1 hour |
| 39473 |
faenuccio author:faenuccio |
feat(Topology.Homeomorph.Lemmas): add lemmas about `coe` and `IsHomeomorph` |
Add lemmas `IsHomeomorph.coe_equiv` and `IsHomeomorph.coe_inv`
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
7/1 |
Mathlib/Topology/Homeomorph/Lemmas.lean |
1 |
2 |
['ADedecker', 'github-actions'] |
alreadydone assignee:alreadydone |
2-1383 2 days ago |
13-22826 13 days ago |
13-22595 13 days |
| 39903 |
akiezun author:akiezun |
feat(NumberTheory): add almost prime numbers |
Adds Nat.IsAlmostPrime k n for natural numbers with exactly k prime factors counted with multiplicity, plus
Nat.IsAtMostAlmostPrime and Nat.IsSemiprime. The definitions reuse the existing arithmetic function Ω, and the initial
API proves the basic zero/one cases, prime examples, and closure under multiplication.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-number-theory
|
87/0 |
Mathlib.lean,Mathlib/NumberTheory/AlmostPrime.lean |
2 |
5 |
['SnirBroshi', 'akiezun', 'github-actions', 'vihdzp'] |
loefflerd assignee:loefflerd |
2-1379 2 days ago |
3-3451 3 days ago |
3-3220 3 days |
| 39950 |
SnirBroshi author:SnirBroshi |
feat(GroupTheory/Nilpotent): a nontrivial nilpotent group has a nontrivial center |
and a few `upperCentralSeries`/`lowerCentralSeries` API lemmas.
---
I kinda thought this would have a more elementary proof, but that's what I found.
This is the proof without `grind`:
```lean
theorem Group.IsNilpotent.center_ne_bot [Nontrivial G] [IsNilpotent G] : center G ≠ ⊥ := by
rw [← upperCentralSeries_zero, ← upperCentralSeries_one]
intro h
rw [upperCentralSeries.eq_top one_ne_zero h, upperCentralSeries_zero] at h
exact top_ne_bot h
```
[](https://gitpod.io/from-referrer/)
|
t-group-theory |
39/2 |
Mathlib/GroupTheory/Nilpotent.lean |
1 |
6 |
['SnirBroshi', 'github-actions', 'tb65536'] |
tb65536 assignee:tb65536 |
2-685 2 days ago |
2-17624 2 days ago |
2-17393 2 days |
| 39953 |
plp127 author:plp127 |
feat(RingTheory/Valuation): embedding of valuation groups |
We show that if `vR` and `vA` are valuations satisfying `vR.HasExtension vA`, then there is an induced embedding of the valuation groups compatible with the valuations and with the extension.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
39/1 |
Mathlib/Algebra/Group/WithOne/Defs.lean,Mathlib/RingTheory/Valuation/Extension.lean |
2 |
2 |
['github-actions', 'plp127'] |
nobody |
1-86158 1 day ago |
2-4 1 day ago |
1-86219 1 day |
| 39892 |
SnirBroshi author:SnirBroshi |
feat(GroupTheory/Commutator/Basic): more commutator identities |
From [Wikipedia](https://en.wikipedia.org/wiki/Commutator#Identities_(group_theory))
---
The last two aren't on Wikipedia but they're similar to Hall-Witt.
[](https://gitpod.io/from-referrer/)
|
t-group-theory |
44/0 |
Mathlib/GroupTheory/Commutator/Basic.lean |
1 |
5 |
['SnirBroshi', 'github-actions', 'tb65536'] |
tb65536 assignee:tb65536 |
1-86020 1 day ago |
3-4364 3 days ago |
3-4133 3 days |
| 36507 |
BryceT233 author:BryceT233 |
feat(RingTheory/MvPowerSeries): various equivalences for `MvPowerSeries` |
This PR adds a number of equivalences related to power series rings and is patterned after `Mathlib/Algebra/MvPolynomial/Equiv.lean`.
To be specific, it adds:
* `MvPowerSeries.isEmptyEquiv` : The isomorphism between multivariable power series
in no variables and the ground ring.
* `MvPowerSeries.uniqueEquiv` : The isomorphism between multivariable power series
in a single variable and power series over the ground ring.
* `MvPowerSeries.mapEquiv`, `MvPowerSeries.mapAlgEquiv` : The isomorhism between
multivariable power series induced by an isomorphism between the coefficient rings.
* `MvPowerSeries.sumAlgEquiv` : The isomorphism between multivariable power series
in a sum of two types, and multivariable power series in one of the types,
with coefficients in multivariable power series in the other type.
* `MvPowerSeries.commAlgEquiv` : The isomorphism between multivariable power series
in variables `σ` of multivariable power series in variables `τ` and multivariable power series
in variables `τ` of multivariable power series in variables `σ`.
* `MvPowerSeries.optionEquivLeft` : The isomorphism between multivariable power series
in `Option σ` and power series with coefficients in `MvPowerSeries σ R`.
* `MvPowerSeries.optionEquivRight` : The isomorphism between multivariable power series
in `Option σ` and multivariable power series in `σ` with coefficients in `PowerSeries R`
* `MvPowerSeries.finSuccEquiv` : The isomorphism between multivariable power series
in `Fin (n + 1)` and power series over multivariable power series in `Fin n`.
---
[](https://gitpod.io/from-referrer/)
- [x] depends on: #35329
- [x] depends on: #36506 |
t-ring-theory |
596/4 |
Mathlib/RingTheory/MvPowerSeries/Basic.lean,Mathlib/RingTheory/MvPowerSeries/Equiv.lean |
2 |
27 |
['AntoineChambert-Loir', 'BryceT233', 'Thmoas-Guan', 'WenrongZou', 'YaelDillies', 'eric-wieser', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
mattrobball assignee:mattrobball |
1-77442 1 day ago |
1-77497 1 day ago |
52-30341 52 days |
| 38200 |
Parcly-Taxel author:Parcly-Taxel |
feat: Turán numbers and their strict monotonicity |
`strictMonoOn_turanNumber` was initially proved by @Aristotle-Harmonic, then hand-polished.
Co-authored-by: Aristotle (Harmonic) |
t-combinatorics |
45/21 |
Mathlib/Combinatorics/SimpleGraph/Extremal/Turan.lean |
1 |
5 |
['Parcly-Taxel', 'github-actions', 'mathlib-merge-conflicts', 'tb65536'] |
nobody |
1-75865 1 day ago |
1-75904 1 day ago |
40-18367 40 days |
| 38086 |
dagurtomas author:dagurtomas |
feat(CategoryTheory): composition of profunctors |
---
- [x] depends on: #38085
- [x] depends on: #38382
[](https://gitpod.io/from-referrer/)
|
t-category-theory |
365/0 |
Mathlib.lean,Mathlib/CategoryTheory/Profunctor/Comp.lean,Mathlib/Logic/Relation.lean |
3 |
16 |
['adamtopaz', 'dagurtomas', 'github-actions', 'mathlib-dependent-issues', 'robin-carlier'] |
robin-carlier assignee:robin-carlier |
1-71143 1 day ago |
1-70887 1 day ago |
15-10992 15 days |
| 37700 |
IvanRenison author:IvanRenison |
feat(Combinatorics/SimpleGraph/Maps): induce an iso |
Similar to `induceHom`
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
31/0 |
Mathlib/Combinatorics/SimpleGraph/Maps.lean |
1 |
12 |
['YaelDillies', 'github-actions', 'vlad902'] |
YaelDillies assignee:YaelDillies |
1-70714 1 day ago |
4-14664 4 days ago |
53-34335 53 days |
| 39133 |
Thmoas-Guan author:Thmoas-Guan |
feat(Algebra/ModuleCat): exactness of restrictScalars for general universe level |
Currently exactness of `ModuleCat.restrictScalars` is synth via being adjoint functor, however this needs the universe level to be some `max u v` where `u` is the universe level of the ring. Here we provide exactness of restrictScalars for general universe level using it preserves short exact sequence.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
46/0 |
Mathlib.lean,Mathlib/Algebra/Category/ModuleCat/ChangeOfRingsExact.lean |
2 |
1 |
['github-actions'] |
nobody |
1-70360 1 day ago |
19-76357 19 days ago |
19-76126 19 days |
| 37374 |
NoneMore author:NoneMore |
feat(Topology/DerivedSet): add relative derived set lemmas |
Add `relDerivedSet`, `relDerivedSet_subset`, and `IsClosed.relDerivedSet_eq`.
---
[](https://gitpod.io/from-referrer/)
|
t-topology
new-contributor
|
17/0 |
Mathlib/Topology/DerivedSet.lean |
1 |
7 |
['NoneMore', 'github-actions', 'plp127', 'vihdzp'] |
fpvandoorn assignee:fpvandoorn |
1-68500 1 day ago |
1-68568 1 day ago |
59-33042 59 days |
| 38583 |
kim-em author:kim-em |
feat(LinearAlgebra/Matrix/GeneralLinearGroup): polynomial functions on matrices over an infinite field are determined by their values on GL |
This PR adds `MvPolynomial.eq_of_eval_eq_on_gl`: two polynomials in `MvPolynomial (m × m) k` over an infinite field `k` are equal whenever their evaluations agree at every invertible matrix.
The proof multiplies by the generic determinant `det (Matrix.mvPolynomialX m m k)` so that `MvPolynomial.funext` applies (covering both invertible and non-invertible specializations of the variables), then divides by it (it is nonzero by `Matrix.det_mvPolynomialX_ne_zero`) using that the polynomial ring is an integral domain.
The lemma is useful when reasoning about polynomial representations of `GL n k`, where natural identities are easiest to check on `GL n k` itself but the final statement lives at the level of polynomials.
The lemma is placed in a new file `Mathlib/LinearAlgebra/Matrix/GeneralLinearGroup/MvPolynomial.lean` because the existing `Mathlib/LinearAlgebra/Matrix/MvPolynomial.lean` is upstream of `Adjugate`, which is itself upstream of `GeneralLinearGroup.Defs` — so we cannot import `GeneralLinearGroup.Defs` from `Matrix.MvPolynomial` without creating a cycle.
🤖 Prepared with Claude Code |
t-algebra
maintainer-merge
label:t-algebra$ |
60/0 |
Mathlib.lean,Mathlib/LinearAlgebra/Matrix/GeneralLinearGroup/MvPolynomial.lean,Mathlib/LinearAlgebra/Matrix/MvPolynomial.lean |
3 |
10 |
['SnirBroshi', 'dagurtomas', 'github-actions', 'kim-em', 'wwylele'] |
dagurtomas assignee:dagurtomas |
1-68360 1 day ago |
2-19423 2 days ago |
18-4254 18 days |
| 38596 |
JJYYY-JJY author:JJYYY-JJY |
Add basic row-equivalence and echelon-form API for matrices |
This PR adds the first foundational slice of `Mathlib.LinearAlgebra.Matrix.Echelon`, a theorem-oriented API for elementary row operations, row-equivalence, and echelon-form predicates for matrices.
The main additions are:
* elementary row-scaling matrices and their `GL` versions;
* `Matrix.RowEquivalent` for the left action of `GL m R` on rectangular matrices;
* row-zero, pivot, echelon, and reduced-echelon predicates;
* semantic representative predicates `Matrix.IsEchelonFormOf` and `Matrix.IsReducedEchelonFormOf`.
This intentionally stops before row-space characterizations, existence and uniqueness of reduced echelon representatives, and the noncomputable canonical representative `Matrix.rref`; those are planned for later PRs.
Co-authored-by: Joseph Qian
Co-authored-by: Veer Shukla
Co-authored-by: Dhruv Bhatia
Co-authored-by: Zheng Wu <1036819072@qq.com>
---
This update trims the original full row-reduction API in response to reviewer feedback that the PR was too large. It keeps only the foundation needed by later row-reduction and `rref` PRs. |
t-algebra
new-contributor
label:t-algebra$ |
312/6 |
Mathlib.lean,Mathlib/LinearAlgebra/Matrix/Echelon.lean,Mathlib/LinearAlgebra/Matrix/Transvection.lean |
3 |
10 |
['JJYYY-JJY', 'SnirBroshi', 'copilot-pull-request-reviewer', 'dagurtomas', 'github-actions', 'wwylele'] |
nobody |
1-67963 1 day ago |
16-7489 16 days ago |
23-69081 23 days |
| 39841 |
hawkrobe author:hawkrobe |
feat(RingTheory/HopfAlgebra): Construction on primitive elements |
Adds `HopfAlgebra.ofPrimitives` which builds a Hopf algebra structure on a bialgebra generated by primitive elements, given a candidate anti-algebra hom that sends each generator to its negation.
---
The commutative case with `.ofAlgHom` gets this for free via `ext` but the non-commutative case needs extra work.
* [ ] depends on: #39785 |
t-ring-theory
new-contributor
|
314/20 |
Mathlib.lean,Mathlib/RingTheory/Bialgebra/Primitive.lean,Mathlib/RingTheory/HopfAlgebra/Basic.lean,Mathlib/RingTheory/HopfAlgebra/Generators.lean,Mathlib/RingTheory/HopfAlgebra/Primitive.lean,Mathlib/RingTheory/HopfAlgebra/TensorProduct.lean |
6 |
2 |
['github-actions'] |
nobody |
1-65098 1 day ago |
2-27056 2 days ago |
4-24241 4 days |
| 38027 |
8e7 author:8e7 |
feat(Combinatorics/SimpleGraph/Star): define star graphs |
Add a new definition `starGraph` and several key lemmas. Star graphs are a trivial class of tree, often used in constructive proofs regarding trees. An example use case is shown in #38334.
---
All lemmas are hand written first, then golfed with the help of Claude Code.
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
87/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Star.lean |
2 |
41 |
['8e7', 'IvanRenison', 'JovanGerb', 'SnirBroshi', 'b-mehta', 'github-actions', 'vihdzp', 'vlad902'] |
nobody |
1-62114 1 day ago |
43-80517 43 days ago |
45-78551 45 days |
| 38052 |
WenrongZou author:WenrongZou |
feat(FormalGroup): `F(X,0)=X` and `F(0,X)=X` |
In this PR, I prove that given a formal group law `F`, then `F(X,0) = X` and `F(0,X) = X`. And modify the definition of `FormalGroup.Point` to be a subtype. And prove that this subtype is a `AddZeroClass`. Eventually we will prove that this is a `AddGroup`.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
253/33 |
Mathlib/RingTheory/FormalGroup/Basic.lean,Mathlib/RingTheory/MvPowerSeries/Substitution.lean,Mathlib/RingTheory/PowerSeries/Basic.lean,Mathlib/RingTheory/PowerSeries/Evaluation.lean,Mathlib/RingTheory/PowerSeries/Substitution.lean |
5 |
19 |
['WenrongZou', 'eric-wieser', 'github-actions', 'mariainesdff', 'mathlib-merge-conflicts'] |
mattrobball assignee:mattrobball |
1-60576 1 day ago |
1-60617 1 day ago |
44-71403 44 days |
| 39949 |
thorimur author:thorimur |
chore: respect naming conventions for defs in more meta code |
This PR removes underscores from various metaprogramming `defs` which were misnamed.
Sometimes meta-level tactic API is named to reflect the tactic syntax, and sometimes expressions representing proofs are named with underscores; but both of these are ordinary parts of the API which should respect ordinary naming conventions for defs.
Note that this PR also renames a couple of definitions in `Mathlib.Tactic.Linarith.NNRealPreprocesser` and `Mathlib.Tactic.Linarith.Preprocessing` to more closely reflect their type (e.g. using `?` for `Option`, `get` instead of `is` for computing data; also `Proof` instead of `Prf` to avoid the unnecessary abbreviation).
These are exempted by the `defsWithUnderscore` linter due to living in `Mathlib.Tactic`. (A change to this is explored in #39890, which removes this heuristic.)
---
[](https://gitpod.io/from-referrer/)
|
t-meta
maintainer-merge
|
63/36 |
Mathlib/Tactic/CategoryTheory/BicategoryCoherence.lean,Mathlib/Tactic/CategoryTheory/Coherence.lean,Mathlib/Tactic/Choose.lean,Mathlib/Tactic/ComputeDegree.lean,Mathlib/Tactic/Linarith/NNRealPreprocessor.lean,Mathlib/Tactic/Linarith/Preprocessing.lean,Mathlib/Tactic/Ring/Compare.lean |
7 |
5 |
['b-mehta', 'github-actions', 'grunweg', 'thorimur'] |
dwrensha assignee:dwrensha |
1-57769 1 day ago |
2-13624 2 days ago |
2-15414 2 days |
| 38228 |
kim-em author:kim-em |
ci: block merging PRs that increase technical debt unless reviewed |
This PR adds a merge gate for technical debt increases.
When the existing technical debt metrics script reports an increase, the `build` job adds an `increases-technical-debt` label. A `check-technical-debt` job then adds `blocked-by-increases-technical-debt`, which blocks bors.
A reviewer can add `allow-increases-technical-debt` to unblock after confirming the increase is acceptable.
### Fail-closed detection
The detection greps for the *safe* patterns (`Decrease in tech debt:` / `No changes to technical debt.`) rather than for `Increase`. If `mathlib-ci` changes the script's output wording, the label is added (fail closed) rather than silently skipped (fail open).
### Labels (three-label pattern, same as #38225)
| Label | Managed by | Purpose |
|---|---|---|
| `increases-technical-debt` | `build` job (tech debt script) | Factual: this PR increases debt |
| `blocked-by-increases-technical-debt` | `check-technical-debt` job | Operational: blocks bors |
| `allow-increases-technical-debt` | Reviewer | Override: reviewer approves the increase |
Bors's `block_labels` has no conditional logic, so we need the derived `blocked-by-increases-technical-debt` label to express the conjunction "increases-technical-debt AND NOT allow-increases-technical-debt".
False positives can be reported on the [mathlib4 Zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/increases-technical-debt.20label).
🤖 Prepared with Claude Code
-----------
- [x] depends on: leanprover-community/mathlib-ci#28 |
CI |
83/2 |
.github/workflows/PR_summary.yml,bors.toml |
2 |
9 |
['github-actions', 'grunweg', 'jcommelin', 'joneugster', 'kim-em', 'mathlib-dependent-issues'] |
Vierkantor and jcommelin assignee:Vierkantor assignee:jcommelin |
1-56493 1 day ago |
1-56493 1 day ago |
14-45568 14 days |
| 38594 |
ScottCarnahan author:ScottCarnahan |
feat(Algebra/Lie): grading on loop algebras |
In this PR we introduce a decomposition of a tensor product of modules induced by a decomposition of the module on the left side. This is used to produce the canonical "energy" grading on a loop Lie algebra. This will (eventually) give us the "energy" grading on smooth representations of affine algebras.
---
Should I make the tensor decomposition more ring-polymorphic?
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
144/9 |
Mathlib/Algebra/Lie/Loop.lean,Mathlib/LinearAlgebra/DirectSum/TensorProduct.lean,Mathlib/LinearAlgebra/TensorProduct/Decomposition.lean,Mathlib/LinearAlgebra/TensorProduct/Map.lean |
4 |
1 |
['github-actions'] |
ocfnash assignee:ocfnash |
1-54075 1 day ago |
2-3158 2 days ago |
2-2948 2 days |
| 39966 |
chrisflav author:chrisflav |
chore(Algebra/Exact): relate surjectivity / injectivity and exactness |
This came up while reviewing #39520, but ended up unnecessary.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
8/0 |
Mathlib/Algebra/Exact.lean |
1 |
1 |
['github-actions'] |
nobody |
1-52099 1 day ago |
1-52172 1 day ago |
1-51941 1 day |
| 39203 |
FordUniver author:FordUniver |
refactor(Analysis/Calculus/Gradient): ungate `inner_gradient` lemmas |
Removes superfluous differentiability hypotheses (plus `UniqueDiffWithinAt` for the `Within` versions) from the four `inner_gradient[Within]_[left|right]` lemmas: `gradient` is defined as `(toDual 𝕜 F).symm (fderiv 𝕜 f x)`, so `⟪∇ f x, y⟫ = fderiv 𝕜 f x y` holds unconditionally since both sides are zero when `f` is not differentiable at `x`.
Co-authored-by: Sebastian Pokutta <23001135+pokutta@users.noreply.github.com>
---
Genuinely unsure about this one because the only call I currently have in my code itself has the differentiability hypothesis. But including unused (or unnecessary) assumptions seems not intentional? My best guess is that the hypotheses were included by analogy with `HasGradientAt.fderiv_apply`, which genuinely needs them. This PR drops the hypotheses and rewrites the proofs through the isomorphism directly; no existing mathlib callers pass the now-redundant arguments. |
t-analysis
maintainer-merge
|
17/10 |
Mathlib/Analysis/Calculus/Gradient/Basic.lean |
1 |
6 |
['FordUniver', 'Komyyy', 'github-actions'] |
urkud assignee:urkud |
1-51815 1 day ago |
18-40614 18 days ago |
18-40383 18 days |
| 39202 |
FordUniver author:FordUniver |
feat(Analysis/Calculus/Gradient): add `toDual_gradient` and companions |
Add `toDual_gradient`, `toDual_gradientWithin`, and the composed variants `toDual_comp_gradient`, `toDual_comp_gradientWithin` — the natural inverse direction of the gradient's defining equation `∇ f x := (toDual 𝕜 F).symm (fderiv 𝕜 f x)`. These identify `(toDual 𝕜 F) (∇ f x)` with `fderiv 𝕜 f x` (and the `gradientWithin` and composed forms with the corresponding fderiv versions), making the Riesz isomorphism between the two derivative views explicit. The proofs of `DifferentiableAt.hasGradientAt` and `DifferentiableWithinAt.hasGradientWithinAt` in the same file are simplified to use them.
Co-authored-by: Sebastian Pokutta <23001135+pokutta@users.noreply.github.com>
---
Came up while formalizing the descent lemma for Lipschitz-smooth functions, where being able to switch between `LipschitzWith K (fderiv ℝ f)` and `LipschitzWith K (∇ f)` is helpful, which with this PR becomes `toDual_comp_gradient ▸ (toDual ℝ F).isometry.lipschitzWith_iff K`. Also slightly simplifies two call sites in mathlib. |
maintainer-merge |
20/5 |
Mathlib/Analysis/Calculus/Gradient/Basic.lean |
1 |
5 |
['FordUniver', 'Komyyy', 'github-actions'] |
nobody |
1-51807 1 day ago |
18-40088 18 days ago |
18-40021 18 days |
| 31892 |
jsm28 author:jsm28 |
feat(Geometry/Euclidean/Sphere/PolePolar): poles and polars |
Define poles and polars for spheres in Euclidean affine spaces, and set up some basic API, including in particular La Hire's theorem (`p₁` lies on the polar of `p₂` if and only if `p₂` lies on the polar of `p₁`).
Poles and polars are actually meaningful for any quadric in a projective space over any field, but I think it's reasonable to set up this theory for spheres in the Euclidean context and potentially link it in future to more general projective geometry.
---
- [x] depends on: #31891
- [x] depends on: #32296
[](https://gitpod.io/from-referrer/)
|
t-euclidean-geometry |
159/0 |
Mathlib.lean,Mathlib/Geometry/Euclidean/Sphere/PolePolar.lean |
2 |
8 |
['Parcly-Taxel', 'github-actions', 'jsm28', 'kim-em', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
nobody |
1-48353 1 day ago |
63-26485 63 days ago |
63-27014 63 days |
| 39707 |
sorrachai author:sorrachai |
chore(Data/Tree/Basic): Rename Tree to BinaryTree |
Rename `Tree` to `BinaryTree`.
This frees up the name `Tree` to cover n-ary trees in future.
We only deprecate the `def`s, and move the theorems without deprecation. |
new-contributor
t-data
|
157/62 |
Mathlib/Combinatorics/Enumerative/Catalan/Tree.lean,Mathlib/Combinatorics/Enumerative/DyckWord.lean,Mathlib/Data/Tree/Basic.lean,Mathlib/Data/Tree/Get.lean,Mathlib/Data/Tree/Traversable.lean,Mathlib/Tactic/CancelDenoms/Core.lean,docs/overview.yaml |
7 |
36 |
['b-mehta', 'eric-wieser', 'github-actions', 'sorrachai'] |
nobody |
1-47635 1 day ago |
5-38867 5 days ago |
5-52694 5 days |
| 36739 |
mbkybky author:mbkybky |
feat(RingTheory): UFD criteria via height `1` prime ideals and localization |
We prove the following UFD criteria via height `1` prime ideals and localization:
1. Let `R` be a Noetherian domain. Then `R` is a UFD if and only if every height `1` prime ideal is principal.
2. Let `R` be a Noetherian domain, `x ∈ R` be a prime element. If `Rₓ` is a UFD, then `R` is also a UFD.
- [x] depends on: #37627
- [x] depends on: #38933
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
208/2 |
Mathlib.lean,Mathlib/RingTheory/Ideal/Height.lean,Mathlib/RingTheory/Ideal/Maximal.lean,Mathlib/RingTheory/Ideal/UFD.lean,Mathlib/RingTheory/Localization/Away/Basic.lean,Mathlib/RingTheory/Localization/Away/Lemmas.lean,Mathlib/RingTheory/UniqueFactorizationDomain/Localization.lean |
7 |
28 |
['chrisflav', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mbkybky', 'tb65536'] |
chrisflav assignee:chrisflav |
1-47487 1 day ago |
3-69924 3 days ago |
67-46659 67 days |
| 39970 |
chrisflav author:chrisflav |
perf(AlgebraicGeometry): specialize index type in `AffineSpace` to `Type u` |
The `AffineSpace` file is notoriously slow and making the index type be in the same universe as the base scheme cuts instructions in half. In case it is necessary, we can still `ULift` to obtain the old functionality.
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-geometry |
27/28 |
Mathlib/AlgebraicGeometry/AffineSpace.lean |
1 |
3 |
['chrisflav', 'github-actions', 'leanprover-radar'] |
nobody |
1-46521 1 day ago |
1-47817 1 day ago |
1-47591 1 day |
| 39785 |
hawkrobe author:hawkrobe |
refactor(RingTheory/HopfAlgebra): `ofConvInverse` constructor |
The antipode of a Hopf algebra is [generally](https://arxiv.org/pdf/1409.8356) the two-sided inverse of the identity in the convolution algebra `End(A)`. When `A` is commutative, algebra homs are closed under convolution and this lifts to AlgHom equality. See [this comment](https://github.com/leanprover-community/mathlib4/pull/31898#issuecomment-3566663278) on #31898.
---
Sadly the AlgHom-equality formulation is unavailable in the noncommutative case.
|
t-ring-theory
new-contributor
maintainer-merge
|
41/20 |
Mathlib/RingTheory/HopfAlgebra/Basic.lean,Mathlib/RingTheory/HopfAlgebra/TensorProduct.lean |
2 |
27 |
['YaelDillies', 'eric-wieser', 'faenuccio', 'github-actions', 'hawkrobe', 'themathqueen'] |
nobody |
1-42348 1 day ago |
1-79304 1 day ago |
4-71972 4 days |
| 39975 |
gasparattila author:gasparattila |
chore: tag `(Continuous)LinearEquiv.prodCongr_symm` with `@[simp]` |
This is consistent with the other `prodCongr`s. Note that this also changes the type of `PiLp.sumPiLpEquivProdLpPiLp_symm_apply_ofLp`, which is now fully simplified.
---
[](https://gitpod.io/from-referrer/)
|
|
5/5 |
Mathlib/LinearAlgebra/Prod.lean,Mathlib/MeasureTheory/Measure/Haar/InnerProductSpace.lean,Mathlib/Topology/Algebra/Module/Equiv.lean |
3 |
1 |
['github-actions'] |
nobody |
1-41587 1 day ago |
1-42156 1 day ago |
1-41925 1 day |
| 39973 |
tb65536 author:tb65536 |
chore(Topology/Algebra/Category/ProfiniteGrp/*): to_additivize some declarations |
This PR to_additivizes some declarations relating to profinite groups. There were a few trickier declarations that I left out of this PR for now.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-group-theory
t-topology
label:t-algebra$ |
28/3 |
Mathlib/Topology/Algebra/Category/ProfiniteGrp/Basic.lean,Mathlib/Topology/Algebra/Category/ProfiniteGrp/Completion.lean,Mathlib/Topology/Algebra/Category/ProfiniteGrp/Limits.lean |
3 |
2 |
['github-actions'] |
nobody |
1-41267 1 day ago |
1-41267 1 day ago |
1-41121 1 day |
| 39977 |
tb65536 author:tb65536 |
feat(RingTheory/RamificationInertia/Ramification): positivity of ramification index |
This PR proves positivity of the new definition ramification inertia.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
t-algebra
label:t-algebra$ |
27/1 |
Mathlib/RingTheory/RamificationInertia/Ramification.lean |
1 |
1 |
['github-actions'] |
nobody |
1-38953 1 day ago |
1-38953 1 day ago |
1-38724 1 day |
| 39206 |
FordUniver author:FordUniver |
feat(Analysis/Calculus/AddTorsor/AffineMap): smoothness of `AffineMap.lineMap` |
Add `AffineMap.lineMap_contDiff_uncurry` (joint smoothness in all three arguments), `AffineMap.lineMap_contDiff` (smoothness in the parameter with fixed endpoints), and the composition family `ContDiff.lineMap`, `ContDiffOn.lineMap`, `ContDiffAt.lineMap`, `ContDiffWithinAt.lineMap`, mirroring the corresponding `Continuous` family in `Mathlib.Topology.Algebra.Affine`. The uncurried and `ContDiffWithinAt` forms are tagged `@[fun_prop]` so the rest are automatically derivable. Closes the TODO at `Mathlib.MeasureTheory.Integral.CurveIntegral.Poincare:333` where the proof now reduces to `fun_prop`.
Co-authored-by: Sebastian Pokutta <23001135+pokutta@users.noreply.github.com>
---
Came up while formalizing the descent lemma for Lipschitz-smooth functions, where `Path.segment a b` being smooth on the unit interval is needed to apply FTC along the segment (#39524); `AffineMap.lineMap_contDiff` is the lemma directly used there. Two things I was genuinely not quite sure about:
1. Should the **three convenience variants** `ContDiffAt.lineMap`, `ContDiffOn.lineMap`, and `ContDiff.lineMap` be included? They are not strictly necessary but they exist for users wanting to write `h₁.lineMap h₂ hg` in dot notation by hand, and they mirror the convention of the `Continuous.lineMap` family.
2. Is `Mathlib.Analysis.Calculus.AddTorsor.AffineMap` the **right home**, and is adding `public import Mathlib.Analysis.Calculus.AddTorsor.AffineMap` to `Poincare.lean` to close the TODO reasonable? The placement mirrors the `Continuous.lineMap` family in `Mathlib.Topology.Algebra.Affine`, but hiding a `@[fun_prop]` in a file at the bottom of the hierarchy and needing to import it feels a bit off. |
t-analysis
maintainer-merge
|
57/6 |
Mathlib/Analysis/Calculus/AddTorsor/AffineMap.lean,Mathlib/MeasureTheory/Integral/CurveIntegral/Poincare.lean |
2 |
8 |
['EtienneC30', 'FordUniver', 'github-actions'] |
EtienneC30 assignee:EtienneC30 |
1-35741 1 day ago |
4-65789 4 days ago |
17-48183 17 days |
| 37183 |
dagurtomas author:dagurtomas |
feat(Tactic/CategoryTheory): map attribute |
Adding `@[map]` to a lemma named `H` of shape `∀ .., f = g`, where `f` and `g` are morphisms
in some category `C`, creates a new lemma named `H_map` of the form
`∀ .. {D} (func : C ⥤ D), F.map f = F.map g` and then applies
`simp only [Functor.map_comp, Functor.map_id]`.
---
[](https://gitpod.io/from-referrer/)
|
LLM-generated
t-meta
t-category-theory
|
301/0 |
Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/CategoryTheory/Map.lean,MathlibTest/CategoryTheory/Map.lean,MathlibTest/CategoryTheory/MapSimp.lean |
5 |
13 |
['adamtopaz', 'dagurtomas', 'github-actions', 'joelriou'] |
kim-em assignee:kim-em |
1-34884 1 day ago |
1-70572 1 day ago |
64-34320 64 days |
| 39122 |
justus-springer author:justus-springer |
feat(AlgebraicGeometry/Birational): Birationality and rationality of schemes |
This is a first step (of hopefully many) towards some basic birational geometry. This PR adds `Birational/Birational.lean`, which defines predicates `Birational`, `BirationalOver` and `IsRationalOver` for arbitrary schemes and provides basic API (e.g. that they are equivalence relations, and that affine space is rational).
Some notes on the choice of definitions: There are multiple ways to define what it means for
two schemes to be birational to each other. A common one is: "There exists a
rational map with a rational inverse". However, this would require defining composition of
rational maps, which is not always defined (In order to compose `f : X ⤏ Y` with `g : Y ⤏ Z`, you
need at least `X` preirreducible, `Y` nonempty and `f` dominant). On the other hand, I can define
"There exist dense subsets `U : Opens X` and `V : Opens Y` such that `U ≅ V` as schemes" for
any two schemes `X` and `Y`, with no conditions. Hence I chose that as a definition. I'm also
working on defining composition of rational maps (#39445), and once that's done, there should be a theorem
connecting the two definitions.
- [x] depends on: #39316
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-geometry |
302/0 |
Mathlib.lean,Mathlib/AlgebraicGeometry/Birational/Birational.lean,Mathlib/AlgebraicGeometry/Restrict.lean |
3 |
12 |
['chrisflav', 'erdOne', 'github-actions', 'justus-springer', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
joelriou assignee:joelriou |
1-33008 1 day ago |
1-51012 1 day ago |
18-78476 18 days |
| 38848 |
jcreinhold author:jcreinhold |
feat(AlgebraicTopology/SimplicialSet): exists_isPushout_of_ne_top |
Every proper subcomplex of a simplicial set extends by attaching a single cell along its boundary, exhibited as a pushout of `∂Δ[n] ↪ Δ[n]`. This is the per-cell input for cell-by-cell filtrations of monomorphisms in `SSet`.
Adapted from @joelriou 's [proof](https://github.com/joelriou/topcat-model-category/blob/813338a8c88cfe0096deed7e3ba7daf92d4a1c71/TopCatModelCategory/SSet/Boundary.lean#L187). I also added the supporting lemma `Types.isPullback_of_eq_setPreimage` (set-preimage square is a pullback in `Type u`).
AI use: Claude helped locate `subtype_val_mono` and the `backward.isDefEq.respectTransparency` option.
|
t-algebraic-topology
new-contributor
|
120/3 |
Mathlib/AlgebraicTopology/SimplicialSet/Boundary.lean,Mathlib/CategoryTheory/Limits/Types/Pullbacks.lean |
2 |
26 |
['github-actions', 'jcreinhold', 'joelriou', 'mckoen'] |
joelriou assignee:joelriou |
1-32961 1 day ago |
20-22916 20 days ago |
26-77862 26 days |
| 37344 |
vihdzp author:vihdzp |
feat: monotone function `Cardinal → α` is eventually constant |
---
- [x] depends on: #39797
[](https://gitpod.io/from-referrer/)
|
t-set-theory
t-order
|
89/1 |
Mathlib.lean,Mathlib/Data/Set/Monotone.lean,Mathlib/Logic/Small/Basic.lean,Mathlib/SetTheory/Cardinal/EventuallyConst.lean |
4 |
5 |
['YaelDillies', 'github-actions', 'mathlib-dependent-issues', 'vihdzp', 'wwylele'] |
nobody |
1-30085 1 day ago |
1-31522 1 day ago |
11-81861 11 days |
| 39790 |
hawkrobe author:hawkrobe |
feat(RingTheory): quotients of coalgebra/bialgebra/Hopf algebras |
---
Adds the quotient constructions suggested [here](https://github.com/leanprover-community/mathlib4/pull/39579#issuecomment-4529401418).
|
t-ring-theory
new-contributor
|
234/0 |
Mathlib.lean,Mathlib/RingTheory/Bialgebra/Quotient.lean,Mathlib/RingTheory/Coalgebra/Quotient.lean,Mathlib/RingTheory/HopfAlgebra/Quotient.lean |
4 |
9 |
['YaelDillies', 'github-actions', 'hawkrobe'] |
nobody |
1-28909 1 day ago |
1-79336 1 day ago |
3-84245 3 days |
| 39982 |
riccardobrasca author:riccardobrasca |
feat: add Ideal.IsPrincipal.of_isPrincipal_pow_of_coprime |
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
31/0 |
Mathlib/RingTheory/ClassGroup.lean |
1 |
1 |
['github-actions'] |
nobody |
1-26697 1 day ago |
1-26593 1 day ago |
1-27216 1 day |
| 39127 |
MichaelStollBayreuth author:MichaelStollBayreuth |
feat(NumberTheory/Height/NumberField): add lemma on "finite part" of mulHeight |
This PR adds
```lean
lemma absNorm_mul_finprod_finitePlace_eq_one {K ι : Type*} [Field K] [NumberField K]
[Finite ι] {x : ι → 𝓞 K} (hx : x ≠ 0) :
(Ideal.span <| Set.range x).absNorm * ∏ᶠ v : FinitePlace K, ⨆ i, v (x i) = 1
```
Because we need it in the proof, we also add a new file Mathlib.Algebra.Order.Hom.Lattice that contains an API lemma that allows reducing the type over which an `iSup` is taken to a subtype.
---
- [x] depends on: #39008
[](https://gitpod.io/from-referrer/)
|
t-number-theory |
70/0 |
Mathlib.lean,Mathlib/Algebra/Order/Hom/Lattice.lean,Mathlib/NumberTheory/Height/NumberField.lean |
3 |
12 |
['MichaelStollBayreuth', 'github-actions', 'mathlib-dependent-issues', 'tb65536'] |
tb65536 assignee:tb65536 |
1-23959 1 day ago |
6-60650 6 days ago |
6-61418 6 days |
| 33355 |
0xTerencePrime author:0xTerencePrime |
feat(Combinatorics/SimpleGraph/Connectivity): define vertex connectivity |
**AI Disclosure**: Developed with LLM assistance (Claude). All mathematical design decisions were made by the author.
---
This PR introduces the foundations of vertex connectivity for simple graphs, providing a counterpart to the edge connectivity theory in #32870.
### Main definitions
- `SimpleGraph.IsVertexReachable`: two vertices are `k`-vertex-reachable if they remain reachable after removing any set of strictly fewer than `k` vertices, using `G.induce sᶜ`.
- `SimpleGraph.IsVertexPreconnected`: a graph is `k`-vertex-preconnected if any two vertices are `k`-vertex-reachable.
- `SimpleGraph.IsVertexConnected`: a graph is `k`-vertex-connected if it is `k`-vertex-preconnected and has more than `k` vertices (`k + 1 ≤ ENat.card V`).
### Key lemmas
- `k = 0`: 0-connected ↔ nonempty; 0-preconnected always holds
- `k = 1`: 1-connected ↔ `Nontrivial V ∧ G.Preconnected`
- `anti` / `mono`: antitonic in `k`, monotonic in the graph |
new-contributor
t-combinatorics
LLM-generated
|
169/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/VertexConnectivity.lean |
2 |
165 |
['0xTerencePrime', 'SnirBroshi', 'SproutSeeds', 'YaelDillies', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp'] |
b-mehta assignee:b-mehta |
1-22318 1 day ago |
3-74386 3 days ago |
62-17027 62 days |
| 39991 |
Brian-Nugent author:Brian-Nugent |
chore(Topology): refactor TopologicalSpace.Opens.map to use OrderHom.toFunctor |
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
27/16 |
Mathlib/Geometry/RingedSpace/OpenImmersion.lean,Mathlib/Geometry/RingedSpace/PresheafedSpace/Gluing.lean,Mathlib/Topology/Category/TopCat/Opens.lean,Mathlib/Topology/Sheaves/Presheaf.lean |
4 |
1 |
['github-actions'] |
nobody |
1-19009 1 day ago |
1-19039 1 day ago |
1-18808 1 day |
| 39807 |
vihdzp author:vihdzp |
feat: universe-heterogeneous cardinal equality |
We introduce a predicate `LiftEq a b`, with notation `a =ₗ b`, which states that two cardinals (in different universes) are equal. This serves as a single canonical spelling for `lift.{v} a = lift.{u} b` and similar incantations.
Future PRs will introduce the analogous predicates for `<` and `≤`, and a notation typeclass so the notation can be reused for `Ordinal` and `OrderType`.
---
[](https://gitpod.io/from-referrer/)
|
t-set-theory |
319/152 |
Mathlib/Algebra/FreeAlgebra/Cardinality.lean,Mathlib/CategoryTheory/Abelian/GrothendieckCategory/EnoughInjectives.lean,Mathlib/FieldTheory/IsAlgClosed/Classification.lean,Mathlib/LinearAlgebra/Dimension/Basic.lean,Mathlib/LinearAlgebra/Dimension/Constructions.lean,Mathlib/LinearAlgebra/Dimension/Free.lean,Mathlib/LinearAlgebra/Dimension/FreeAndStrongRankCondition.lean,Mathlib/LinearAlgebra/Dimension/LinearMap.lean,Mathlib/LinearAlgebra/Dimension/StrongRankCondition.lean,Mathlib/ModelTheory/Basic.lean,Mathlib/ModelTheory/Satisfiability.lean,Mathlib/RingTheory/AlgebraicIndependent/Basic.lean,Mathlib/RingTheory/AlgebraicIndependent/RankAndCardinality.lean,Mathlib/RingTheory/AlgebraicIndependent/TranscendenceBasis.lean,Mathlib/RingTheory/LinearDisjoint.lean,Mathlib/RingTheory/Localization/Cardinality.lean,Mathlib/SetTheory/Cardinal/Aleph.lean,Mathlib/SetTheory/Cardinal/Arithmetic.lean,Mathlib/SetTheory/Cardinal/Basic.lean,Mathlib/SetTheory/Cardinal/Defs.lean,Mathlib/SetTheory/Cardinal/ENat.lean,Mathlib/SetTheory/Cardinal/Order.lean,Mathlib/SetTheory/Cardinal/ToNat.lean,Mathlib/SetTheory/Ordinal/Univ.lean,Mathlib/SetTheory/ZFC/Cardinal.lean |
25 |
2 |
['acmepjz', 'github-actions'] |
nobody |
1-17708 1 day ago |
4-26338 4 days ago |
4-26349 4 days |
| 39399 |
Brian-Nugent author:Brian-Nugent |
feat(Algebra/CategoryTheory/ModuleCat): Locally Free Sheaves |
This PR gives a definition of locally free sheaves in terms of first defining a predicate IsLocallyFree for [SheafOfModules.LocalGeneratorsData](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Algebra/Category/ModuleCat/Sheaf/Generators.html#SheafOfModules.LocalGeneratorsData).
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-category-theory
label:t-algebra$ |
212/5 |
Mathlib.lean,Mathlib/Algebra/Category/ModuleCat/Sheaf/Generators.lean,Mathlib/Algebra/Category/ModuleCat/Sheaf/LocallyFree.lean,Mathlib/Algebra/Category/ModuleCat/Sheaf/Quasicoherent.lean |
4 |
12 |
['Brian-Nugent', 'dagurtomas', 'github-actions', 'mathlib-merge-conflicts', 'robin-carlier'] |
dagurtomas assignee:dagurtomas |
1-10707 1 day ago |
1-10707 1 day ago |
6-71828 6 days |
| 28613 |
espottesmith author:espottesmith |
feat(Combinatorics): define undirected hypergraphs |
This PR defines undirected hypergraphs:
```
@[ext]
structure Hypergraph (α : Type*) where
/-- The vertex set -/
vertexSet : Set α
/-- The hyperedge set -/
hyperedgeSet : Set (Set α)
/-- All hyperedges must be subsets of the vertex set -/
hyperedge_isSubset_vertexSet : ∀ ⦃e⦄, e ∈ hyperedgeSet → e ⊆ vertexSet
```
In addition to the main definition, some additional definitions and related lemmas are provided:
- vertex adjacency
- hyperedge adjacency
- vertex "stars"
- special cases (loops, empty hypergraphs, trivial hypergraphs, complete hypergraphs, simple hypergraphs, k-uniform hypergraphs, and d-regular hypergraphs)
- (some) hypergraph cardinality
- subhypergraphs, induced subhypergraphs, and partial hypergraphs
This implementation is certainly bare-bones. I'm submitting this PR at this point, rather than when my developments are more fleshed out, because there has been some interest in others contributing to hypergraph formalization in mathlib.
In the near future, goals include:
- defining incidence matrices (i.e., conversion from `Hypergraph α` to `Matrix α (Set α) β`
- coersion/generalization of graph as 2-uniform hypergraph
- conversion of a hypergraph into its associated clique graph/two-section graph
- constructing the dual of a hypergraph (note: on first blush, this appears somewhat challenging, given that we define hyperedges as `Set α` rather than some other type `β`)
- rank and co-rank
- walks, paths, cycles, etc. on hypergraphs
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
286/0 |
Mathlib.lean,Mathlib/Combinatorics/Hypergraph/Basic.lean |
2 |
152 |
['SnirBroshi', 'b-mehta', 'espottesmith', 'github-actions', 'jt496', 'lauramonk', 'mathlib4-merge-conflict-bot', 'tb65536'] |
b-mehta assignee:b-mehta |
1-10355 1 day ago |
2-21955 2 days ago |
104-10373 104 days |
| 39629 |
hawkrobe author:hawkrobe |
feat(RingTheory/Coalgebra/Convolution): Algebra on convolution semiring |
This PR completes the algebraic structure on the convolution object.
---
I followed the pattern in [`Matrix/WithConv.lean`](https://github.com/leanprover-community/mathlib4/blob/5e932f97dd25535344f80f9dd8da3aab83df0fe6/Mathlib/LinearAlgebra/Matrix/WithConv.lean#L98) which splits out `IsScalarTower` and `SMulCommClass`. Used in pre-Lie / Oudom–Guin constructions. |
t-ring-theory
new-contributor
|
24/1 |
Mathlib/RingTheory/Coalgebra/Convolution.lean |
1 |
2 |
['github-actions'] |
nobody |
1-10195 1 day ago |
9-22137 9 days ago |
9-21906 9 days |
| 32294 |
jsm28 author:jsm28 |
feat(Geometry/Euclidean/Angle/Incenter): distance from second intersection with circumcircle |
Add the following lemma: given a triangle ABC, suppose an angle bisector from A through the incenter or excenter I meets the circumcircle again at X (including the case of an external bisector at A tangent to the circle, in which case X = A). Then XB = XI (= XC, by applying this lemma again). This is a standard configuration: https://en.wikipedia.org/wiki/Incenter%E2%80%93excenter_lemma
---
- [ ] depends on: #30981
- [ ] depends on: #30982
- [ ] depends on: #32019
- [ ] depends on: #32021
- [ ] depends on: #32023
- [ ] depends on: #32270
- [ ] depends on: #32290
[](https://gitpod.io/from-referrer/)
|
t-euclidean-geometry |
214/0 |
Mathlib/Geometry/Euclidean/Angle/Incenter.lean |
1 |
5 |
['github-actions', 'jsm28', 'mathlib-dependent-issues', 'mathlib4-merge-conflict-bot', 'peakpoint'] |
nobody |
1-9743 1 day ago |
1-9812 1 day ago |
63-26902 63 days |
| 39997 |
Whysoserioushah author:Whysoserioushah |
feat(LinearAlgebra/Projectivization/Action): More about PSL actions on projective space |
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
79/0 |
Mathlib/LinearAlgebra/Projectivization/Action.lean |
1 |
1 |
['github-actions'] |
nobody |
1-4816 1 day ago |
1-4895 1 day ago |
1-4664 1 day |
| 36963 |
seewoo5 author:seewoo5 |
feat(ModularForms): SL2 action and Serre derivative |
---
[](https://gitpod.io/from-referrer/)
Equivariance of Serre derivative under SL2 action. More precisely, $$\partial_k (F|_k \gamma) = (\partial_{k} F)|_{k+2} \gamma$$. From [Sphere Packing Project](https://github.com/thefundamentaltheor3m/Sphere-Packing-Lean). |
t-number-theory
large-import
|
124/24 |
Mathlib/Analysis/Complex/UpperHalfPlane/Manifold.lean,Mathlib/Analysis/Complex/UpperHalfPlane/MoebiusAction.lean,Mathlib/NumberTheory/ModularForms/Derivative.lean |
3 |
12 |
['github-actions', 'loefflerd', 'mathlib-merge-conflicts', 'seewoo5', 'tb65536', 'wwylele'] |
tb65536 assignee:tb65536 |
1-3863 1 day ago |
1-7888 1 day ago |
27-1133 27 days |
| 38840 |
peabrainiac author:peabrainiac |
feat(Topology): continuous germs of maps |
Add a predicate `Filter.Germ.Continuous` for continuity of germs between topological spaces, and bundled types `ContinuousGerm x Y` / `PointedContinuousGerm x y` of continuous germs at `x` resp. continuous germs at `x` taking `x` to `y`.
---
See also #10977, which tried to introduce smooth germs between manifolds a while ago, though with a focus on pointwise algebraic operations instead of composability.
[](https://gitpod.io/from-referrer/)
|
t-topology |
171/1 |
Mathlib.lean,Mathlib/Topology/ContinuousGerm.lean,Mathlib/Topology/ContinuousOn.lean,Mathlib/Topology/Germ.lean |
4 |
6 |
['chrisflav', 'github-actions', 'j-loreaux', 'mathlib-merge-conflicts', 'peabrainiac'] |
nobody |
1-2538 1 day ago |
11-4173 11 days ago |
23-38708 23 days |
| 38886 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Function/SimpleFuncDenseLp` |
- rewrites `measure_preimage_lt_top_of_memLp` via `FinMeasSupp.of_lintegral_ne_top` and `FinMeasSupp.map_iff`, instead of expanding `eLpNorm'` and splitting through `ENNReal.mul_lt_top_iff`
Extracted from #38104
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
t-measure-probability
|
9/21 |
Mathlib/MeasureTheory/Function/SimpleFuncDenseLp.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
nobody |
1-2533 1 day ago |
26-41678 26 days ago |
26-41447 26 days |
| 36103 |
SnkXyx author:SnkXyx |
feat(Algebra/MvPolynomial/CharacteristicSet): add Characteristic Set |
This PR adds some definitions and theorems of Characteristic Set Method (also known as Wu's Method).
Definitions:
* `MvPolynomial.mainDegree`
* `MvPolynomial.initialOf`
* `MvPolynomial.reducedTo`
* `TriangulatedSet`
* `MvPolynomial.pseudo`
* `MvPolynomial.setPseudo`
* `MvPolynomial.isRemainder`
* `MvPolynomial.isSetRemainder`
* `AscendingSetTheory`
* `TriangulatedSet.isAscendingSet`
* `HasBasicSet`
* `TriangulatedSet.isCharacteristicSet`
* `MvPolynomial.List.characteristicSet`
* `MvPolynomial.List.zeroDecomposition`
Main Theorems:
* `MvPolynomial.initialOf_mul_eq`: $init_i(p \cdot q) = init_i(p) \cdot init_i(q)$ if there is no zero divisors in the coefficient ring.
* `TriangulatedSet.instWellFoundedLT`: The set of Triangulated Sets is well-founded under the lexicographic ordering.
* `MvPolynomial.pseudo_remainder_isRemainder`: The remainder $r$ of $g$ by $f$ is reduced with respect to $f$ and satisfies $init(f)^s \cdot g = q \cdot f + r$ for some $s \in \mathbb{N}$ and $q \in R[X_{\sigma}]$.
* `MvPolynomial.setPseudo_remainder_isSetRemainder`: The remainder $r$ of $g$ by a set $S$ is reduced with respect to $S$ and satisfies $(\prod S_i^{e_i}) \cdot g = \sum q_i \cdot S_i + r$ for some sequences $\{e_i\}$ and $\{q_i\}$.
* `MvPolynomial.setPseudo_remainder_eq_zero_of_mem`: The remainder of $p$ by a set $S$ is $0$ if $p \in S$.
* `MvPolynomial.List.basicSet_append_lt_of_exists_reducedToSet`: Appending an element which is reduced w.r.t. the basic set of list strictly decreases the order.
* `MvPolynomial.List.characteristicSet_isCharacteristicSet`: The computed Characteristic Set $CS$ satisfies the key algebraic property (pseudo-remainder of input polynomials is 0) and the geometric property ( $Zero(PS) \subseteq Zero(CS)$ ).
* `MvPolynomial.List.vanishingSet_eq_zeroDecomposition_union`: The zero set of a polynomial system $PS$ can be decomposed into a finite union of "quasi-varieties" defined by triangular sets:
$Zero(PS) = \bigcup_{CS \in \mathcal{ZD}} Zero(CS / \text{InitialProd}(CS))$
The PR is upstreamized from [github.com/WuProver/lean_characteristic_set](https://github.com/WuProver/lean_characteristic_set)
---
[](https://gitpod.io/from-referrer/)
- [x] depends on: #36386
- [x] depends on: #37791
|
t-algebra
new-contributor
label:t-algebra$ |
3860/0 |
Mathlib.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/AscendingSet.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/CharacteristicSet.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/Initial.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/MainDegree.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/Order.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/PseudoDivision.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/Reduce.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/StandardAscendingSet.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/TriangularSet.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/WeakAscendingSet.lean,docs/references.bib |
12 |
21 |
['Hagb', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
dagurtomas assignee:dagurtomas |
1-964 1 day ago |
3-75600 3 days ago |
26-43090 26 days |
| 37914 |
j-loreaux author:j-loreaux |
feat: transfer `star`-related instances across equivalences |
This also adds `Function.Injective.{InvolutiveStar,...}` and related lemmas.
In addition we rename the existing `Equiv.star` to `Equiv.Perm.star` (without a deprecation) so that the name can be used for the declaration which transfers a `Star` instance across an `Equiv`.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
maintainer-merge
label:t-algebra$ |
95/2 |
Mathlib.lean,Mathlib/Algebra/Star/Basic.lean,Mathlib/Algebra/Star/Pointwise.lean,Mathlib/Algebra/Star/TransferInstance.lean |
4 |
15 |
['SnirBroshi', 'github-actions', 'themathqueen'] |
dagurtomas assignee:dagurtomas |
1-963 1 day ago |
36-28629 36 days ago |
36-30307 36 days |
| 38009 |
CBirkbeck author:CBirkbeck |
feat(RingTheory/Valuation): define the valuation spectrum and its topology |
## Summary
Define the valuation spectrum `Spv A` of a commutative ring and equip it with the topology generated by basic open sets, following Wedhorn's *Adic Spaces*. Also define the pullback (`comap`) of a `ValuativeRel` along a ring homomorphism. This is preparation for later defining adic spaces.
Note the code was generated by claude code, but I have cleaned up and pre-reviewed the work.
|
t-ring-theory
LLM-generated
|
362/0 |
Mathlib.lean,Mathlib/RingTheory/Valuation/ValuationSpectrum.lean,Mathlib/RingTheory/Valuation/ValuativeRel/Comap.lean |
3 |
40 |
['CBirkbeck', 'adamtopaz', 'chrisflav', 'dagurtomas', 'faenuccio', 'github-actions', 'jjdishere', 'riccardobrasca'] |
alreadydone assignee:alreadydone |
1-962 1 day ago |
45-49302 45 days ago |
45-49224 45 days |
| 38098 |
astrainfinita author:astrainfinita |
chore: make `SMul.comp.smul` `implicit_reducible` |
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
2/1 |
Mathlib/Algebra/Group/Action/Defs.lean |
1 |
3 |
['astrainfinita', 'github-actions', 'leanprover-radar'] |
kim-em assignee:kim-em |
1-961 1 day ago |
43-78696 43 days ago |
43-78465 43 days |
| 38169 |
tb65536 author:tb65536 |
chore(GroupTheory/Finiteness): make `Subgroup.FG` a class |
This PR refactors `Subgroup.FG` to be a class to match `Group.FG`.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-group-theory
label:t-algebra$ |
37/20 |
Mathlib/GroupTheory/Commutator/Finite.lean,Mathlib/GroupTheory/Finiteness.lean,Mathlib/GroupTheory/Rank.lean,Mathlib/GroupTheory/Schreier.lean |
4 |
10 |
['JovanGerb', 'github-actions', 'mathlib-bors', 'riccardobrasca', 'tb65536'] |
mattrobball assignee:mattrobball |
1-960 1 day ago |
28-40041 28 days ago |
42-27969 42 days |
| 38324 |
BryceT233 author:BryceT233 |
chore(RingTheory/AdicCompletion): make `AdicCompletion.map` linear on linear maps |
This PR upgrades `AdicCompletion.map` to be an R-linear map on the space of linear maps `M →ₗ[R] N`.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
38/12 |
Mathlib/RingTheory/AdicCompletion/Basic.lean,Mathlib/RingTheory/AdicCompletion/Functoriality.lean |
2 |
2 |
['github-actions', 'mathlib-merge-conflicts'] |
alreadydone assignee:alreadydone |
1-958 1 day ago |
36-4924 36 days ago |
38-73799 38 days |
| 38380 |
linesthatinterlace author:linesthatinterlace |
feat(Data/Set): add Set.diag API |
Introduces `Set.diag (s : Set α) : Set (α × α) = {(a, a) | a ∈ s}` as the set-level companion to `Set.offDiag`, mirroring the existing `Finset.diag` / `Finset.offDiag` pairing. The type-level `Set.diagonal : Type* → Set (α × α)` is retained unchanged; `diag_univ : (univ : Set α).diag = diagonal α` (`@[simp]`) keeps it canonical when the underlying set is `univ`.
Parallels to the existing `offDiag` API (`diag_mono`, `diag_nonempty`, `diag_eq_empty`, `diag_empty`, `diag_singleton`, `diag_subset_prod`, `diag_eq_sep_prod`, `diag_inter`, `diag_union`, `diag_insert`) plus bridges `diag_union_offDiag`, `disjoint_diag_offDiag`, `prod_sdiff_diag`, `prod_sdiff_offDiag`. Also `diag_eq_image`, `image_diag` (matching `Finset.image_diag`), `preimage_coe_coe_diag`, and `Finset.coe_diag`. Note `diag_union` and `diag_insert` are unconditional (no `Disjoint` / `a ∉ s` hypothesis).
To free the `diag_` prefix for the set sense, the existing lemmas about the diagonal *map* `fun x => (x, x)` are renamed with deprecation aliases:
`range_diag` → `range_diagMap`, `diag_preimage_prod` → `diagMap_preimage_prod`, `diag_preimage_prod_self` → `diagMap_preimage_prod_self`. `diag_image` and `preimage_coe_coe_diagonal` are marked `@[deprecated]`.
This PR was prepared with the assistance of Claude Opus. |
t-data
LLM-generated
|
124/15 |
Mathlib/Data/Finset/Prod.lean,Mathlib/Data/Set/Operations.lean,Mathlib/Data/Set/Prod.lean,Mathlib/MeasureTheory/MeasurableSpace/Constructions.lean,Mathlib/Topology/Compactness/Compact.lean,Mathlib/Topology/Compactness/Lindelof.lean,Mathlib/Topology/NhdsSet.lean |
7 |
2 |
['github-actions', 'linesthatinterlace'] |
TwoFX assignee:TwoFX |
1-957 1 day ago |
37-19055 37 days ago |
37-18824 37 days |
| 38741 |
eric-wieser author:eric-wieser |
feat: Nat.card lemmas for Sym and Sym2 |
These are just translations of the `Fintype` counterparts.
---
[](https://gitpod.io/from-referrer/)
|
t-data
maintainer-merge
|
109/7 |
Mathlib.lean,Mathlib/Data/Sym/Card.lean,Mathlib/Data/Sym/NatCard.lean,Mathlib/Data/Sym/Sym2.lean |
4 |
26 |
['SnirBroshi', 'YaelDillies', 'eric-wieser', 'github-actions', 'mathlib-merge-conflicts'] |
joneugster assignee:joneugster |
1-956 1 day ago |
3-59542 3 days ago |
25-52513 25 days |
| 38830 |
Jun2M author:Jun2M |
feat(Data/List): Nodup and head & getLast lemmas |
Given a Nodup list:
* If a prefix contains the last element, they are equal
* If a suffix contains the first element, they are equal
* If an infix contains the first element, it is a prefix
* If an infix contains the last element, it is a suffix
* If the first and the last element are the same, it is a singleton
* `countP` is cardinality of the filter of `toFinset`.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
29/0 |
Mathlib/Data/Finset/Card.lean,Mathlib/Data/List/Nodup.lean |
2 |
7 |
['SnirBroshi', 'github-actions', 'mathlib-merge-conflicts'] |
joneugster assignee:joneugster |
1-955 1 day ago |
8-20650 8 days ago |
24-5230 24 days |
| 39347 |
Sfgangloff author:Sfgangloff |
feat(SymbolicDynamics): refactor of Pattern and shift-invariance of shape languages for subshifts |
## Summary
This PR refactors Pattern.mulShift in Mathlib/Dynamics/SymbolicDynamics/Basic.lean and uses the cleaner definition to prove shift-invariance of the language of a subshift on a finite shape.
## Changes
Pattern.mulShift now returns a Pattern instead of a configuration (more natural).
- Old type: Pattern.mulShift : Pattern A G → G → (G → A)
- New type: Pattern.mulShift : Pattern A G → G → Pattern A G
- The result carries its support (p.support.image (v * ·)) and the
default-outside-support proof, so callers don't have to re-derive them.
The [IsLeftCancelMul G] hypothesis is moved to the lemmas that actually use it.
- The definition Pattern.mulShift itself no longer needs left-cancellation (it only
chooses a preimage noncomputably).
- The hypothesis is now stated on mulShift_config_apply_mul_left_of_mem and
mulOccursInAt_eq_cylinder directly, instead of being a section-level variable.
Renames following the type change.
- mulShift_apply_mul_left_of_mem → mulShift_config_apply_mul_left_of_mem (because we
now write (p.mulShift v).config instead of p.mulShift v).
New @[simp] and @[ext] lemmas for Pattern.
- Pattern.ext: two patterns are equal iff their supports agree and their
configurations agree on the support.
- Pattern.mulShift_support: the support of p.mulShift v is p.support.image (v * ·).
- Pattern.fromConfig_support: the support of fromConfig x U is U.
- Pattern.fromConfig_config_of_mem: on its support, fromConfig x U agrees with x.
New lemma Pattern.fromConfig_mulShift.
For a left inverse g' * g = 1, shifting the pattern fromConfig x U by g equals
fromConfig (mulShift g' x) (U.image (g * ·)).
New theorem MulSubshift.languageOn_image_mulShift.
For a subshift Y and elements g, g' with g * g' = 1 and g' * g = 1:
(fun p => p.mulShift g) '' Y.languageOn U = Y.languageOn (U.image (g * ·))
i.e. the language on the translated shape is exactly the image of the language on U
under the pattern-shift map. This gives a bijection between Y.languageOn U and
Y.languageOn (U.image (g * ·)), with inverse p ↦ p.mulShift g'. Stated for
left-cancellative monoids with an invertible element.
Updated docstrings for Pattern.mulShift and the renamed lemma to reflect the
bundled-Pattern return type and clarify which results need [IsLeftCancelMul G]. |
t-dynamics
new-contributor
|
142/48 |
Mathlib/Dynamics/SymbolicDynamics/Basic.lean |
1 |
3 |
['github-actions'] |
sgouezel assignee:sgouezel |
1-953 1 day ago |
15-82645 15 days ago |
15-82414 15 days |
| 39588 |
jvanwinden author:jvanwinden |
feat(MeasureTheory/Measure/ProbabilityMeasure): add toProbabilityMeasure and basic API |
Introduces `Measure.toProbabilityMeasure`, which converts a `Measure` into a `ProbabilityMeasure` in the presence of the typeclass assumption `[IsProbabilityMeasure]`. Some basic API is added for the interaction between `toProbabilityMeasure` and the coercion from `ProbabilityMeasure` to `Measure`. The main convenience is that the new method allows for dot notation on `Measure`.
This PR arose from the following situation: I needed to prove equality of two `Measure` objects, and I wanted to do this by using uniqueness of limits. But the topology of weak convergence is only defined on `ProbabilityMeasure` and not on `Measure`. With the new lemma `toProbabilityMeasure_inj`, an equality of measures can easily be rewritten into an equality of the corresponding probability measures, after which `tendsto_nhds_unique` can be applied.
Aside from this, `toProbabilityMeasure` has the potential to simplify theorem statements about `Measure` objects which use the topology of weak convergence either in the assumptions or the conclusion. For example, now one can simply write `Tendsto μ.toProbabilityMeasure f (nhds μ_lim.toProbabilityMeasure)` when appropriate `[IsProbabilityMeasure]` assumptions are present.
This PR is intended as a starting point for a discussion. I only added some basic API, but perhaps more lemmas should be added (which ones?). Also, a similar definition could be made for `FiniteMeasure`.
---
[](https://gitpod.io/from-referrer/)
|
t-measure-probability |
19/2 |
Mathlib/MeasureTheory/Measure/ProbabilityMeasure.lean |
1 |
1 |
['github-actions'] |
kex-y assignee:kex-y |
1-952 1 day ago |
10-23523 10 days ago |
10-23292 10 days |
| 39882 |
chrisflav author:chrisflav |
chore(CategoryTheory): `StructuredArrow.map₂` along equivalences induces an equivalence |
Before that we only had an instance `IsEquivalence`, this provides the full equivalence with good def-eqs for the inverse.
---
[](https://gitpod.io/from-referrer/)
|
t-category-theory
maintainer-merge
|
126/2 |
Mathlib/CategoryTheory/Comma/StructuredArrow/Basic.lean |
1 |
7 |
['chrisflav', 'github-actions', 'robin-carlier'] |
robin-carlier assignee:robin-carlier |
1-948 1 day ago |
2-18590 2 days ago |
3-30607 3 days |
| 39951 |
chrisflav author:chrisflav |
refactor(CategoryTheory/Sites): replace `Functor.inducedTopology` |
The current `Functor.inducedTopology` is only defined for a locally fully faithful and locally cover dense functor and in the general situation it does not make the functor continuous. We change the situation in two ways:
- Replace `Functor.inducedTopology` by the induced topology in the sense of SGA, III, 3.1: The finest topology on the domain making a functor continuous.
- Add `Functor.restrictedTopology`: This is the coarsest topology on the domain containing all sieves whose image generates a covering sieve in the codomain. In general, a functor does not preserve covers for this topology and in particular is not necessarily continuous.
The old `Functor.inducedTopology` is equal (but not def-eq) to the new `Functor.restrictedTopology` whenever the old definition applies. In the situation where `Functor.restrictedTopology` makes the functor continuous, for example when `F` is flat, locally fully faithful and locally cover dense, the two topologies agree.
Related Zulip discussion: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Induced.20topology.20on.20a.20category/with/593098526
From Proetale.
---
- [ ] depends on: #39961
[](https://gitpod.io/from-referrer/)
|
t-category-theory |
294/122 |
Mathlib.lean,Mathlib/AlgebraicGeometry/Sites/Affine.lean,Mathlib/AlgebraicGeometry/Sites/AffineEtale.lean,Mathlib/AlgebraicGeometry/Sites/Proetale.lean,Mathlib/AlgebraicGeometry/Sites/Small.lean,Mathlib/AlgebraicGeometry/Sites/SmallAffineZariski.lean,Mathlib/CategoryTheory/MorphismProperty/CommaSites.lean,Mathlib/CategoryTheory/Sites/Coherent/Equivalence.lean,Mathlib/CategoryTheory/Sites/Coherent/SheafComparison.lean,Mathlib/CategoryTheory/Sites/DenseSubsite/InducedTopology.lean,Mathlib/CategoryTheory/Sites/Equivalence.lean,Mathlib/CategoryTheory/Sites/InducedTopology.lean |
12 |
3 |
['dagurtomas', 'github-actions', 'mathlib-dependent-issues'] |
robin-carlier assignee:robin-carlier |
1-945 1 day ago |
1-10920 1 day ago |
1-15003 1 day |
| 39959 |
chrisflav author:chrisflav |
chore(CategoryTheory/Sites): make auxiliary declarations for `OneHypercoverDenseData.isSheaf_iff` private |
---
[](https://gitpod.io/from-referrer/)
|
t-category-theory
maintainer-merge
|
7/7 |
Mathlib/CategoryTheory/Sites/DenseSubsite/OneHypercoverDense.lean |
1 |
2 |
['github-actions', 'grunweg'] |
robin-carlier assignee:robin-carlier |
1-943 1 day ago |
1-62690 1 day ago |
1-62459 1 day |
| 39987 |
vihdzp author:vihdzp |
chore: golf `Ordinal.cof_univ` |
---
(I think this is my second time golfing this one theorem, sorry!)
[](https://gitpod.io/from-referrer/)
|
t-set-theory
easy
|
1/4 |
Mathlib/SetTheory/Cardinal/Cofinality/Ordinal.lean |
1 |
1 |
['github-actions', 'plp127'] |
nobody |
0-84353 23 hours ago |
1-23119 1 day ago |
1-22888 1 day |
| 39958 |
BryceT233 author:BryceT233 |
feat(RingTheory/Kaehler/JacobiZariski): exactness at the left of Jacobi-Zariski sequence under flatness assumption |
Given algebras `R → S → T` and `T` flat over `S`, this PR adds the exactness of `T ⊗[S] H₁(L_{S/R}) → H₁(L_{T/R}) → H₁(L_{T/S})` at the left of Jacobi-Zariski sequence. Note that the flatness assumption here is stronger than the Tor-vanishing conditions required in the full statement of [Stacks Project, 00S2](https://stacks.math.columbia.edu/tag/00S2), this should be refactored and generalized once more results on Tor modules are available.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
70/0 |
Mathlib/RingTheory/Kaehler/JacobiZariski.lean |
1 |
1 |
['github-actions'] |
nobody |
0-82406 22 hours ago |
1-66976 1 day ago |
1-66745 1 day |
| 36643 |
Thmoas-Guan author:Thmoas-Guan |
feat(Homology): interaction of projective and injective dimension and SES |
In this PR, we directly implemented the relation of `projectiveDimension` and `injectiveDimension` in SES.
---
- [x] depends on: #36817
[](https://gitpod.io/from-referrer/)
|
t-category-theory |
182/0 |
Mathlib/Algebra/Homology/ShortComplex/Exact.lean,Mathlib/CategoryTheory/Abelian/Injective/Dimension.lean,Mathlib/CategoryTheory/Abelian/Projective/Dimension.lean |
3 |
6 |
['dagurtomas', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
adamtopaz assignee:adamtopaz |
0-79772 22 hours ago |
0-80719 22 hours ago |
45-53430 45 days |
| 32058 |
Thmoas-Guan author:Thmoas-Guan |
feat(Algebra): Baer criterion for injective dimension |
In this PR, we added the cateory version of Baer criterion stating that `M` is injective iff `Ext^1(R/I, M)` vanish for all ideal `I`. By dimension shifting, we also have `M` has injective dimension not exceeding `n` iff `Ext^{n + 1}(R/I, M)` vanish for all ideal `I`.
---
- [x] depends on: #36980
- [x] depends on: #39305
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-category-theory
label:t-algebra$ |
160/0 |
Mathlib.lean,Mathlib/Algebra/Category/ModuleCat/Ext/Baer.lean |
2 |
79 |
['Thmoas-Guan', 'dagurtomas', 'github-actions', 'joelriou', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib-splicebot', 'mathlib4-merge-conflict-bot'] |
joelriou assignee:joelriou |
0-79112 21 hours ago |
0-80825 22 hours ago |
66-32993 66 days |
| 39994 |
Brian-Nugent author:Brian-Nugent |
feat(CategoryTheory): Functors that preserve the terminal object are Final |
---
[](https://gitpod.io/from-referrer/)
|
t-category-theory |
21/1 |
Mathlib/CategoryTheory/Limits/Final.lean,Mathlib/CategoryTheory/Sites/CoproductSheafCondition.lean |
2 |
1 |
['github-actions'] |
nobody |
0-77103 21 hours ago |
0-77180 21 hours ago |
0-79019 21 hours |
| 38890 |
SnirBroshi author:SnirBroshi |
feat(Order/ConditionallyCompleteLattice/Basic): more `WithTop` instances |
Adds the following instances:
```
CompleteLattice α → CompleteLattice (WithTop α)
CompleteLinearOrder α → CompleteLinearOrder (WithBot α)
ConditionallyCompleteLinearOrder α → ConditionallyCompleteLinearOrder (WithTop α)
ConditionallyCompleteLinearOrder α → ConditionallyCompleteLinearOrderBot (WithBot α)
```
and some simp lemmas to help.
---
These `#synth`s all succeed after this PR:
(code)
```lean
variable {α : Type*} [Preorder α]
#synth Preorder αᵒᵈ
#synth Preorder <| WithTop α
#synth Preorder <| WithBot α
#synth Preorder <| WithTopBot α
#synth Preorder <| WithBotTop α
variable {α : Type*} [PartialOrder α]
#synth PartialOrder αᵒᵈ
#synth PartialOrder <| WithTop α
#synth PartialOrder <| WithBot α
#synth PartialOrder <| WithTopBot α
#synth PartialOrder <| WithBotTop α
variable {α : Type*} [LinearOrder α]
#synth LinearOrder αᵒᵈ
#synth LinearOrder <| WithTop α
#synth LinearOrder <| WithBot α
#synth LinearOrder <| WithTopBot α
#synth LinearOrder <| WithBotTop α
variable {α : Type*} [CompleteLattice α]
#synth CompleteLattice αᵒᵈ
#synth CompleteLattice <| WithTop α -- new
#synth CompleteLattice <| WithBot α
#synth CompleteLattice <| WithTopBot α
#synth CompleteLattice <| WithBotTop α
variable {α : Type*} [CompleteLinearOrder α]
#synth CompleteLinearOrder αᵒᵈ
#synth CompleteLinearOrder <| WithTop α
#synth CompleteLinearOrder <| WithBot α -- new
#synth CompleteLinearOrder <| WithTopBot α
#synth CompleteLinearOrder <| WithBotTop α
variable {α : Type*} [ConditionallyCompleteLattice α]
#synth ConditionallyCompleteLattice αᵒᵈ
#synth ConditionallyCompleteLattice <| WithTop α
#synth ConditionallyCompleteLattice <| WithBot α
#synth CompleteLattice <| WithTopBot α
#synth CompleteLattice <| WithBotTop α
variable {α : Type*} [ConditionallyCompleteLinearOrder α]
#synth ConditionallyCompleteLinearOrder αᵒᵈ
#synth ConditionallyCompleteLinearOrder <| WithTop α -- new
#synth ConditionallyCompleteLinearOrderBot <| WithBot α -- new
#synth CompleteLinearOrder <| WithTopBot α
#synth CompleteLinearOrder <| WithBotTop α
variable {α : Type*} [ConditionallyCompleteLinearOrderBot α]
#synth ConditionallyCompleteLinearOrder αᵒᵈ
#synth CompleteLinearOrder <| WithTop α
#synth ConditionallyCompleteLinearOrderBot <| WithBot α -- new
#synth CompleteLinearOrder <| WithTopBot α
#synth CompleteLinearOrder <| WithBotTop α
```
|
t-order
maintainer-merge
|
89/69 |
Mathlib/Order/ConditionallyCompleteLattice/Basic.lean |
1 |
5 |
['SnirBroshi', 'YaelDillies', 'github-actions'] |
YaelDillies assignee:YaelDillies |
0-75327 20 hours ago |
0-75337 20 hours ago |
24-12568 24 days |
| 39992 |
Brian-Nugent author:Brian-Nugent |
feat(CategoryTheory/Order): Lattice Homs preserve limits and colimits |
Provides instances for when [OrderHom.toFunctor](https://leanprover-community.github.io/mathlib4_docs/Mathlib/CategoryTheory/Category/Preorder.html#OrderHom.toFunctor) preserves limits and colimits.
---
[](https://gitpod.io/from-referrer/)
|
t-category-theory
t-order
|
105/0 |
Mathlib.lean,Mathlib/CategoryTheory/Limits/Preserves/Lattice.lean |
2 |
2 |
['dagurtomas', 'github-actions'] |
nobody |
0-75077 20 hours ago |
0-75068 20 hours ago |
0-77831 21 hours |
| 40002 |
mcdoll author:mcdoll |
chore(Analysis/TemperedDistribution): generalize to TVS codomains |
Obviously the codomain of a tempered distribution should be allowed to be an arbitrary topological vector space
---
[](https://gitpod.io/from-referrer/)
|
t-analysis |
60/21 |
Mathlib/Analysis/Distribution/TemperedDistribution.lean |
1 |
1 |
['github-actions'] |
nobody |
0-69280 19 hours ago |
0-69365 19 hours ago |
0-69134 19 hours |
| 39720 |
vihdzp author:vihdzp |
feat: cofinality within order |
We introduce `Order.cofWithin x = Order.cof (Iio x)` for the cofinality of an element within a preorder. This generalizes `Ordinal.cof`, with the caveat that `cof o : Cardinal.{u}` for `o : Ordinal.{u}`, whereas `cofWithin o : Cardinal.{u + 1}`.
---
[](https://gitpod.io/from-referrer/)
|
t-set-theory
maintainer-merge
|
104/14 |
Mathlib/SetTheory/Cardinal/Basic.lean,Mathlib/SetTheory/Cardinal/Cofinality/Basic.lean,Mathlib/SetTheory/Cardinal/Cofinality/Ordinal.lean |
3 |
11 |
['SnirBroshi', 'YaelDillies', 'b-mehta', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp'] |
nobody |
0-67190 18 hours ago |
3-74132 3 days ago |
7-13370 7 days |
| 39928 |
Vierkantor author:Vierkantor |
feat(Tactic): `convert` discharges side goals reducibly |
This PR implements the main behaviour change from #39039: `convert` now discharges side goals at reducible transparency. `convert!`, which we previously switched all calls inside Mathlib to, keeps the old behaviour of working at default transparency. (Everything discussed in this PR holds analogously for the other tactics in the family: `convert_to` and `ac_change`).
The main trick in this PR is in allowing `convert!` to have different configuration options than `convert`, but still allow the user to override those options too. So `convert! (postTransparency := .instances)` will have transparency set to `.instances`, not `.default`. We achieve this by having two new structures that copy `Congr!.Config` but set different default values, and choosing between the corresponding elaborators for those configs based on the presence of an `!`. I got this trick from Jovan's #38071 which also changes settings in `Convert.Config`.
This PR should be mostly compatible with #38071 and I'd like to get both this one and #38071 in before wrapping up #39039 by replacing unnecessary calls to `convert!` with `convert`.
---
[](https://gitpod.io/from-referrer/)
|
t-meta |
165/47 |
Mathlib/Algebra/Lie/Weights/Chain.lean,Mathlib/Algebra/Lie/Weights/Killing.lean,Mathlib/AlgebraicGeometry/Morphisms/UniversallyOpen.lean,Mathlib/AlgebraicGeometry/Normalization.lean,Mathlib/AlgebraicGeometry/OpenImmersion.lean,Mathlib/AlgebraicGeometry/PointsPi.lean,Mathlib/AlgebraicGeometry/StructureSheaf.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/PUnit.lean,Mathlib/AlgebraicTopology/SimplicialSet/Nerve.lean,Mathlib/Analysis/CStarAlgebra/ContinuousFunctionalCalculus/Unique.lean,Mathlib/Analysis/Calculus/Deriv/Inverse.lean,Mathlib/Analysis/Fourier/FourierTransformDeriv.lean,Mathlib/Analysis/Normed/Module/FiniteDimension.lean,Mathlib/CategoryTheory/Galois/Decomposition.lean,Mathlib/Combinatorics/SimpleGraph/Trails.lean,Mathlib/FieldTheory/IntermediateField/ExtendRight.lean,Mathlib/NumberTheory/DiophantineApproximation/Basic.lean,Mathlib/NumberTheory/Padics/PadicNumbers.lean,Mathlib/Order/Filter/AtTopBot/Finite.lean,Mathlib/RepresentationTheory/Action.lean,Mathlib/RingTheory/GradedAlgebra/HomogeneousLocalization.lean,Mathlib/RingTheory/Ideal/KrullsHeightTheorem.lean,Mathlib/RingTheory/Localization/Algebra.lean,Mathlib/RingTheory/Polynomial/GaussNorm.lean,Mathlib/RingTheory/PowerSeries/PiTopology.lean,Mathlib/RingTheory/Valuation/ExtendToLocalization.lean,Mathlib/RingTheory/Valuation/ValuationSubring.lean,Mathlib/Tactic/CongrExclamation.lean,Mathlib/Tactic/Convert.lean,Mathlib/Topology/Category/TopCat/Limits/Products.lean,MathlibTest/Tactic/Convert/Basic.lean,MathlibTest/Tactic/Convert/Bugfix7945.lean,MathlibTest/ValuedCSP.lean |
33 |
1 |
['github-actions'] |
dwrensha assignee:dwrensha |
0-62494 17 hours ago |
1-37328 1 day ago |
1-37099 1 day |
| 40005 |
tautschnig author:tautschnig |
feat(Data/ZMod/Basic): isUnit characterisation in prime power moduli |
Add two lemmas characterising units in ZMod (p^n) via divisibility of the canonical lift:
isUnit_iff_not_prime_dvd_val: for prime p and n > 0,
IsUnit x ↔ ¬ p ∣ x.val.
not_isUnit_iff_prime_dvd_val: for prime p and n > 0,
¬ IsUnit x ↔ p ∣ x.val.
These specialise the existing isUnit_iff_coprime to prime power moduli, where the coprimality condition reduces to a simple divisibility check on the unique prime factor.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
|
15/0 |
Mathlib/Data/ZMod/Basic.lean |
1 |
3 |
['copilot-pull-request-reviewer', 'github-actions'] |
nobody |
0-61490 17 hours ago |
0-63808 17 hours ago |
0-63577 17 hours |
| 40006 |
tautschnig author:tautschnig |
feat(Data/ZMod/Basic): idempotents in ZMod (p^d) are exactly {0, 1} |
Add sq_eq_self_iff_eq_zero_or_one: in ZMod (p^d) for prime p and d > 0, x^2 = x iff x = 0 or x = 1.
This generalises eq_zero_or_one_of_sq_eq_self (which requires CancelMonoidWithZero, i.e., no zero divisors) to the prime-power case. ZMod (p^d) has zero divisors for d >= 2, so the mul_left_injective₀ argument used by the existing lemma does not apply. The proof works by lifting to ℕ, using that if gcd(a, b) = 1 and p^d | a*b then p^d divides one of a or b (by Euclid's lemma), then noting that a = x.val and b = x.val - 1 are consecutive naturals and hence coprime.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
|
56/0 |
Mathlib/Data/ZMod/Basic.lean |
1 |
2 |
['github-actions'] |
nobody |
0-58887 16 hours ago |
0-58957 16 hours ago |
0-59421 16 hours |
| 35672 |
dennj author:dennj |
feat(RingTheory/Polynomial/Cyclotomic): vanishing sums and fiber equidistribution at primitive roots |
## Summary
Building on `sum_eq_zero_iff_forall_eq` from #34592, this PR adds:
- cyclotomic_dvd_of_aeval_eq_zero, exists_int_smul_cyclotomic_of_natDegree_le_totient — integer polynomials vanishing at a primitive n-th root are divisible by cyclotomic n ℤ, and (for degree ≤ φ(n)) integer multiples of it.
- sum_eq_zero_iff_forall_eq and its ℤ / ZMod p variants — vanishing iff all coefficients equal.
- sum_fiber_eq_sum_fiber_of_sum_weighted_pow_eq_zero, card_fiber_eq_card_div_of_sum_pow_eq_zero — fiber equidistribution.
- cyclotomic_prime_coeff — the formula (cyclotomic p R).coeff i = if i < p then 1 else 0, generalising existing coeff_zero/coeff_one lemmas.
-
References: [deLauneyFlannery2011, Lemma 2.8.5] (underlying ℚ/ℕ fact) and [armario2024, Lemma 7 and Theorem 3] (ℤ statement and the fiber-counting application).
Theorems imported from: https://github.com/Latinum-Agentic-Commerce/AlgebraicDesignTheory
Human made PR with LLM used for documentation and proof golfing |
t-ring-theory
new-contributor
LLM-generated
|
128/2 |
Mathlib/RingTheory/Polynomial/Cyclotomic/Basic.lean,Mathlib/RingTheory/Polynomial/Cyclotomic/Roots.lean,docs/references.bib |
3 |
7 |
['dennj', 'github-actions', 'grunweg', 'ocfnash', 'riccardobrasca'] |
riccardobrasca assignee:riccardobrasca |
0-58690 16 hours ago |
24-20142 24 days ago |
42-34021 42 days |
| 37008 |
BryceT233 author:BryceT233 |
feat(RingTheory/LocalRing): `IsLocalRing` for pullbacks |
We provide basic lemmas for equalizers and pullbacks of `RingHom` and `AlgHom`, and show they are local rings under suitable condtions.
This is needed in #37940 to construct a residue algebra structure on pullbacks.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
167/0 |
Mathlib.lean,Mathlib/RingTheory/LocalRing/Pullback.lean |
2 |
6 |
['BryceT233', 'github-actions', 'riccardobrasca', 'wwylele'] |
riccardobrasca assignee:riccardobrasca |
0-58155 16 hours ago |
33-10663 33 days ago |
67-65185 67 days |
| 38002 |
Raph-DG author:Raph-DG |
feat(Topology): Relating irreducible components of a space to codimension one points in non dense subsets |
In this PR we show that the coheight zero points of a sober space (in the specialization order) correspond to the irreducible components. Furthermore, we show that the coheight one points of any non dense subset p of X (in the specialization order on p) have coheight zero in the specialization order on X.
---
[](https://gitpod.io/from-referrer/)
|
large-import
t-topology
|
113/0 |
Mathlib/Order/Hom/Basic.lean,Mathlib/Order/KrullDimension.lean,Mathlib/Order/Minimal.lean,Mathlib/Topology/Inseparable.lean,Mathlib/Topology/Sober.lean |
5 |
7 |
['ADedecker', 'Raph-DG', 'dagurtomas', 'github-actions', 'mathlib-merge-conflicts'] |
dagurtomas assignee:dagurtomas |
0-58009 16 hours ago |
0-58009 16 hours ago |
41-30251 41 days |
| 37975 |
Thmoas-Guan author:Thmoas-Guan |
feat(RingTheory): AdicCompletion of local ring is local |
In this PR, we proved that AdicCompletion of local ring wrt the maximal ideal is local ring with maximal ideal equal to the map of the original maximal ideal.
Also, removing some old junk produced by myself.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
large-import
|
173/5 |
Mathlib/RingTheory/AdicCompletion/LocalRing.lean |
1 |
21 |
['BryceT233', 'Thmoas-Guan', 'github-actions', 'riccardobrasca'] |
riccardobrasca assignee:riccardobrasca |
0-57458 15 hours ago |
46-56123 46 days ago |
46-67686 46 days |
| 39428 |
harahu author:harahu |
chore: add an empty line after module headers |
This makes the docs easier to read.
---
[](https://gitpod.io/from-referrer/)
|
|
120/4 |
Archive/Imo/Imo1998Q2.lean,Archive/Imo/Imo2001Q6.lean,Archive/Imo/Imo2005Q3.lean,Archive/Imo/Imo2008Q2.lean,Archive/Imo/Imo2008Q3.lean,Archive/Imo/Imo2008Q4.lean,Counterexamples/DiscreteTopologyNonDiscreteUniformity.lean,Counterexamples/PeanoCurve.lean,Counterexamples/Pseudoelement.lean,Mathlib/Algebra/Algebra/Spectrum/Basic.lean,Mathlib/Algebra/Category/Grp/EpiMono.lean,Mathlib/Algebra/Category/ModuleCat/Stalk.lean,Mathlib/Algebra/EuclideanDomain/Field.lean,Mathlib/Algebra/EuclideanDomain/Int.lean,Mathlib/Algebra/Homology/Opposite.lean,Mathlib/Algebra/Lie/Cochain.lean,Mathlib/Algebra/Lie/Extension.lean,Mathlib/Algebra/Lie/Loop.lean,Mathlib/Algebra/MonoidAlgebra/PointwiseSMul.lean,Mathlib/Algebra/Order/AddTorsor.lean,Mathlib/Algebra/Order/Archimedean/IndicatorCard.lean,Mathlib/Algebra/Squarefree/Basic.lean,Mathlib/Algebra/Vertex/HVertexOperator.lean,Mathlib/Algebra/Vertex/VertexOperator.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/Product.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/SimplyConnected.lean,Mathlib/Analysis/Analytic/RadiusLiminf.lean,Mathlib/Analysis/Normed/Affine/Convex.lean,Mathlib/Analysis/Normed/Lp/PiLp.lean,Mathlib/Analysis/Normed/Lp/ProdLp.lean,Mathlib/Analysis/Normed/Unbundled/SeminormFromBounded.lean,Mathlib/Analysis/Normed/Unbundled/SmoothingSeminorm.lean,Mathlib/CategoryTheory/DinatTrans.lean,Mathlib/CategoryTheory/Limits/Preserves/Filtered.lean,Mathlib/CategoryTheory/Limits/Shapes/Pullback/HasPullback.lean,Mathlib/CategoryTheory/PathCategory/Basic.lean,Mathlib/CategoryTheory/Preadditive/Schur.lean,Mathlib/CategoryTheory/Sites/Abelian.lean,Mathlib/CategoryTheory/Sites/LeftExact.lean,Mathlib/CategoryTheory/Thin.lean,Mathlib/Combinatorics/Configuration.lean,Mathlib/Data/Bracket.lean,Mathlib/Data/Bundle.lean,Mathlib/Data/Finsupp/BigOperators.lean,Mathlib/Data/Nat/Squarefree.lean,Mathlib/Data/PSigma/Order.lean,Mathlib/Data/SProd.lean,Mathlib/Data/Set/Enumerate.lean,Mathlib/Data/Set/UnionLift.lean,Mathlib/Dynamics/TopologicalEntropy/CoverEntropy.lean,Mathlib/Dynamics/TopologicalEntropy/NetEntropy.lean,Mathlib/Dynamics/TopologicalEntropy/Semiconj.lean,Mathlib/FieldTheory/RatFunc/AsPolynomial.lean,Mathlib/Geometry/Manifold/Algebra/Monoid.lean,Mathlib/Geometry/Manifold/Diffeomorph.lean,Mathlib/Geometry/Manifold/IsManifold/InteriorBoundary.lean,Mathlib/GroupTheory/CommutingProbability.lean,Mathlib/LinearAlgebra/Multilinear/Curry.lean,Mathlib/LinearAlgebra/RootSystem/Finite/CanonicalBilinear.lean,Mathlib/LinearAlgebra/RootSystem/Hom.lean,Mathlib/LinearAlgebra/RootSystem/OfBilinear.lean,Mathlib/LinearAlgebra/RootSystem/RootPairingCat.lean,Mathlib/LinearAlgebra/RootSystem/WeylGroup.lean,Mathlib/Logic/Lemmas.lean,Mathlib/MeasureTheory/Function/EssSup.lean,Mathlib/MeasureTheory/Group/Prod.lean,Mathlib/ModelTheory/PartialEquiv.lean,Mathlib/NumberTheory/ClassNumber/AdmissibleAbs.lean,Mathlib/NumberTheory/ClassNumber/AdmissibleAbsoluteValue.lean,Mathlib/NumberTheory/ClassNumber/Finite.lean,Mathlib/NumberTheory/Cyclotomic/Discriminant.lean,Mathlib/NumberTheory/Cyclotomic/PrimitiveRoots.lean,Mathlib/NumberTheory/FLT/Four.lean,Mathlib/NumberTheory/FLT/Three.lean,Mathlib/NumberTheory/NumberField/Basic.lean,Mathlib/NumberTheory/NumberField/Completion/FinitePlace.lean,Mathlib/NumberTheory/NumberField/Cyclotomic/Basic.lean,Mathlib/NumberTheory/NumberField/Cyclotomic/Embeddings.lean,Mathlib/NumberTheory/NumberField/Cyclotomic/PID.lean,Mathlib/NumberTheory/NumberField/Cyclotomic/Three.lean,Mathlib/NumberTheory/NumberField/Discriminant/Basic.lean,Mathlib/NumberTheory/NumberField/Discriminant/Defs.lean,Mathlib/NumberTheory/NumberField/EquivReindex.lean,Mathlib/NumberTheory/NumberField/ExistsRamified.lean,Mathlib/NumberTheory/NumberField/House.lean,Mathlib/NumberTheory/NumberField/Norm.lean,Mathlib/NumberTheory/NumberField/Units/DirichletTheorem.lean,Mathlib/Order/Bounded.lean,Mathlib/Probability/Distributions/Uniform.lean,Mathlib/RepresentationTheory/Rep/Res.lean,Mathlib/RingTheory/AdicCompletion/RingHom.lean,Mathlib/RingTheory/Conductor.lean,Mathlib/RingTheory/Coprime/Lemmas.lean,Mathlib/RingTheory/DedekindDomain/AdicValuation.lean,Mathlib/RingTheory/DedekindDomain/FiniteAdeleRing.lean,Mathlib/RingTheory/DedekindDomain/Instances.lean,Mathlib/RingTheory/HahnSeries/Addition.lean,Mathlib/RingTheory/HahnSeries/Binomial.lean,Mathlib/RingTheory/HahnSeries/Multiplication.lean,Mathlib/RingTheory/HahnSeries/PowerSeries.lean |
120 |
3 |
['github-actions', 'grunweg', 'mathlib-merge-conflicts'] |
nobody |
0-54820 15 hours ago |
1-64820 1 day ago |
8-32337 8 days |
| 39857 |
plp127 author:plp127 |
chore(Order/CompleteLattice/Basic): `Sort*` polymorphism |
Generalize some theorems from `Type*` to `Sort*`. Also make type-variables explicitly either `Type*` or `Sort*`.
---
[](https://gitpod.io/from-referrer/)
|
t-order |
15/31 |
Mathlib/Order/CompleteLattice/Basic.lean |
1 |
3 |
['SnirBroshi', 'b-mehta', 'github-actions'] |
nobody |
0-52955 14 hours ago |
3-84513 3 days ago |
3-84282 3 days |
| 37521 |
jessealama author:jessealama |
feat(Data/Part): add Part.bind_eq_some_iff |
Add `Part.bind_eq_some_iff`, the `Part` analogue of `Option.bind_eq_some_iff`. Noticed this small gap while working on some equivalence proofs with partial functions. |
t-data
maintainer-merge
|
6/0 |
Mathlib/Data/Part.lean |
1 |
7 |
['github-actions', 'jessealama', 'joneugster', 'vihdzp'] |
joneugster assignee:joneugster |
0-52151 14 hours ago |
11-83404 11 days ago |
54-40006 54 days |
| 36922 |
SnirBroshi author:SnirBroshi |
feat(Data/List/Chain): generalize `WellFounded.asymmetric₃` to chains |
The existing `WellFounded.asymmetric` shows `r a b → ¬r b a`,
and `WellFounded.asymmetric₃` shows `r a b → r b c → ¬r c a`.
This adds `WellFounded.asymmetricₙ` which shows `l.IsChain r → ¬r l.getLast l.head`.
---
Also adds a couple of `IsChain` lemmas which might be useful.
[](https://gitpod.io/from-referrer/)
|
t-data |
29/8 |
Mathlib/Data/List/Chain.lean |
1 |
6 |
['SnirBroshi', 'Vierkantor', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp'] |
eric-wieser assignee:eric-wieser |
0-52002 14 hours ago |
0-52002 14 hours ago |
69-77926 69 days |
| 37534 |
EtienneC30 author:EtienneC30 |
feat: cardinality of subsets of a given cardinality |
Given a finite set `s`, the number of subsets of `s` with cardinality `n` is `s.ncard.choose n`. This is analog to [Finset.card_powersetCard](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Data/Finset/Powerset.html#Finset.card_powersetCard) and [Set.powersetCard.card](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Data/Set/PowersetCard.html#Set.powersetCard.card) but with a set of sets rather than involving finsets.
---
[](https://gitpod.io/from-referrer/)
|
t-data
maintainer-merge
|
22/0 |
Mathlib/Data/Set/Card.lean |
1 |
4 |
['EtienneC30', 'github-actions', 'joneugster'] |
joneugster assignee:joneugster |
0-51722 14 hours ago |
14-42523 14 days ago |
56-45442 56 days |
| 39869 |
grunweg author:grunweg |
doc: clarify the scope of `field_simp` |
The term semi-field is sufficiently non-standard that it has led to confusion whether e.g. `NNReal` is supported by field_simp: it is (as it is a semifield). Let's clarify the doc-string.
Inspired by discussions at the ICERM workshop "Techniques and Tools for the Formalization of Analysis".
---
[](https://gitpod.io/from-referrer/)
|
documentation
easy
t-meta
maintainer-merge
|
4/4 |
Mathlib/Tactic/FieldSimp.lean |
1 |
2 |
['github-actions', 'joneugster'] |
thorimur assignee:thorimur |
0-48810 13 hours ago |
3-45783 3 days ago |
3-45552 3 days |
| 39888 |
adomani author:adomani |
ci(decls-diff): post-build workflow that emits a Lean-aware diff into the step summary |
Stage 2 of the Lean-aware declarations-diff feature. Stage 1 (#39880) made the producer side write `decls.txt` + `imports.json` into the `import-graph` artifact; this PR adds the consumer.
## What this PR adds
A new `.github/workflows/decls-diff.yml` workflow that fires on `workflow_run` completion of the `ci` workflow (PR builds only), and:
1. Resolves the new commit's SHA and the merge-base against master.
2. Downloads the `import-graph` artifact from both sides — the triggering PR run, and the most recent master `ci` run at the merge-base.
3. Sparse-checks-out mathlib's local actions from `${{ github.workflow_sha }}` (the trusted base-branch ref), invokes `get-mathlib-ci`, and then calls leanprover-community/mathlib-ci's [`decls-diff` composite action](https://github.com/leanprover-community/mathlib-ci/pull/43) to compute the diff and render a Markdown body.
4. Writes the rendered diff to that run's `$GITHUB_STEP_SUMMARY`.
If the master-side artifact isn't found for the merge-base (a bors-batch-intermediate cache miss), the step summary gets an explanatory message instead and no further work runs.
## Stage-2 scope: step summary only
There's no `### PR summary` comment patching here. That behaviour ships in stage 3 along with the patcher script. Stage 2 lets reviewers evaluate the rendering quality without us touching PR comments under the bot's identity.
## Security notes
* `Checkout local actions` sparse-checks-out `.github/actions/` from `${{ github.workflow_sha }}` into `workflow-actions/`, so `Get mathlib-ci` resolves against the trusted base-branch copy of the action rather than the PR-branch copy. Same pattern as `build_template.yml`'s `build` job and the `post_steps` `Get mathlib-ci` step added to #39880.
* Cross-repo `decls-diff` action is SHA-pinned to the mathlib-ci PR's branch HEAD (`5802cc4c1d`); `update_dependencies.yml` will roll it forward to the merged-master SHA once leanprover-community/mathlib-ci#43 lands.
* `permissions:` is read-only (`contents: read` for the checkout, `actions: read` for cross-workflow artifact downloads); no write tokens flow to consumers.
* Artifact contents are treated as data — fed to `comm`/`sort`/`sed`/`printf` and emitted verbatim into the step summary. Never executed, never path-interpreted.
## Dependencies
* leanprover-community/mathlib-ci#43 (companion PR; adds the action this workflow invokes).
🤖 Generated with [Claude Code](https://claude.com/claude-code) |
CI
LLM-generated
|
122/0 |
.github/workflows/decls-diff.yml |
1 |
1 |
['github-actions'] |
nobody |
0-47982 13 hours ago |
3-14123 3 days ago |
3-13892 3 days |
| 39876 |
kim-em author:kim-em |
feat(scripts): dump cross-reference tags to TSV for downstream review |
This PR adds `scripts/dump_crossref_tags.lean`, which walks `Mathlib.CrossRef.tagExt` in the elaborated Mathlib environment and writes one TSV record per tagged declaration. The TSV is consumed by a privileged `workflow_run` job that posts the cross-reference review PR comment; the rest of that machinery lives in https://github.com/leanprover-community/external-tags and https://github.com/leanprover-community/mathlib-ci. Fields are sanitised so tabs/newlines in user-controlled comments can't break the TSV framing, and the output is capped at 2 MB.
Uses `importModules (loadExts := true)` rather than `withImportModules`, because the wrapper passes `loadExts := false` and would leave `tagExt` empty for imported modules.
🤖 Prepared with [Claude Code](https://claude.com/claude-code) |
CI
LLM-generated
|
96/0 |
scripts/README.md,scripts/dump_crossref_tags.lean |
2 |
3 |
['github-actions', 'jcommelin', 'kim-em'] |
nobody |
0-47928 13 hours ago |
2-62043 2 days ago |
2-61918 2 days |
| 39954 |
jihuang2024 author:jihuang2024 |
feat(Analysis/Polynomial): define Hurwitz stability and prove small-degree characterizations |
Proofs were developed with assistance from Claude Code. I have reviewed and understand all the code and can justify the design decisions.
This PR introduces the predicate Polynomial.IsHurwitzStable for real polynomials and proves the Routh–Hurwitz stability criterion for degrees 1 and 2.
A polynomial p : ℝ[X] is Hurwitz stable if every root of its complexification has strictly negative real part. This notion arises in control theory and the study of linear ODEs, where it characterises asymptotic stability of a system.
New definitions
Polynomial.IsHurwitzStable: ∀ z : ℂ, (p.map (algebraMap ℝ ℂ)).IsRoot z → z.re < 0
New theorems
Polynomial.not_isHurwitzStable_zero: the zero polynomial is not Hurwitz stable
Polynomial.IsHurwitzStable.ne_zero: Hurwitz stable polynomials are nonzero
Polynomial.isHurwitzStable_X_add_C: X + C a is Hurwitz stable ↔ 0 < a
Polynomial.isHurwitzStable_quadratic: X ^ 2 + C b * X + C c is Hurwitz stable ↔ 0 < b ∧ 0 < c
Proof strategy for the quadratic
The quadratic case splits on whether a root z is real (z.im = 0) or complex (z.im ≠ 0, which forces 2 * z.re + b = 0). Existence of a root uses Complex.exists_root (Fundamental Theorem of Algebra). The necessary condition in the real-root case uses the Vieta complementary root -b - z.re.
Future work
The general Routh–Hurwitz theorem (for degree n, stated in terms of the Hurwitz matrix and its leading principal minors) requires infrastructure not yet in Mathlib — in particular a theory of the Cauchy index or the Bezoutian of two polynomials. This PR lays the definitional foundation for that work.
This corresponds to [1000.yaml](https://github.com/leanprover-community/mathlib4/blob/master/docs/1000.yaml#L2697) Q4455015 - Routh–Hurwitz theorem |
t-analysis
new-contributor
LLM-generated
|
131/0 |
Mathlib.lean,Mathlib/Analysis/Polynomial/RouthHurwitz.lean |
2 |
10 |
['SnirBroshi', 'github-actions', 'jihuang2024', 'wwylele'] |
nobody |
0-44104 12 hours ago |
0-45937 12 hours ago |
1-50733 1 day |
| 39353 |
Raph-DG author:Raph-DG |
feat(Topology): Show existence of a neighbourhood around p which avoids all points in the support of a locally finsupp function except those which specialize to p |
In this PR we show a simple lemma proving the existence of a neighbourhood around any point p which avoids every point in the support of a locally finsupp function except those which specialize to p.
AI disclosure: The statements and a sketch with sorries were provided by me, but I had claude fill in the sorries.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
29/0 |
Mathlib/Topology/LocallyFinsupp.lean |
1 |
1 |
['github-actions'] |
nobody |
0-42539 11 hours ago |
0-42539 11 hours ago |
0-73643 20 hours |
| 40013 |
WilliamCoram author:WilliamCoram |
feat: define bounded sets and power bounded elements |
We define bounded sets, so that we can define power bounded elements in a topological ring. Using this we generalise some notions of topoligcally nilpotent elements and define a residue field.
AI usage: some proofs were initially generated with Claude code before being cleaned and/or rewritten by hand.
---
[](https://gitpod.io/from-referrer/)
|
t-topology
LLM-generated
large-import
|
431/5 |
Mathlib.lean,Mathlib/Topology/Algebra/Bounded.lean,Mathlib/Topology/Algebra/PowerBounded.lean,Mathlib/Topology/Algebra/TopologicallyNilpotent.lean |
4 |
1 |
['github-actions'] |
nobody |
0-42528 11 hours ago |
0-42601 11 hours ago |
0-42882 11 hours |
| 29774 |
Raph-DG author:Raph-DG |
feat(AlgebraicGeometry): Order of vanishing of elements of the function field of locally noetherian, integral schemes |
In this PR, we define the order of vanishing of elements of the function field of locally noetherian, integral schemes at points of codimension 1. This is essentially just a wrapper around the API for the order of vanishing for rings (i.e. Ring.ord and Ring.ordFrac), but I think it's good to have this too for usability.
---
- [ ] depends on: #29550
- [ ] depends on: #26735
[](https://gitpod.io/from-referrer/)
|
t-algebraic-geometry |
99/0 |
Mathlib.lean,Mathlib/AlgebraicGeometry/FunctionField.lean,Mathlib/AlgebraicGeometry/OrderOfVanishing.lean,Mathlib/AlgebraicGeometry/Properties.lean |
4 |
10 |
['Raph-DG', 'dagurtomas', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot'] |
dagurtomas assignee:dagurtomas |
0-42512 11 hours ago |
0-42512 11 hours ago |
30-73671 30 days |
| 40012 |
SnirBroshi author:SnirBroshi |
feat(GroupTheory/PGroup): iSup of normal p-subgroups is a p-subgroup |
Also shows that the `iSup` of subgroups equals the set-union of all finite `iSup`s.
Co-authored-by: Albert Smith <10266947+ChiCubed@users.noreply.github.com>
---
[](https://gitpod.io/from-referrer/)
|
t-group-theory |
34/0 |
Mathlib/Algebra/Group/Subgroup/Pointwise.lean,Mathlib/GroupTheory/PGroup.lean |
2 |
1 |
['github-actions'] |
nobody |
0-42059 11 hours ago |
0-41891 11 hours ago |
0-45813 12 hours |
| 39891 |
SnirBroshi author:SnirBroshi |
feat: the center of a product/pi is the product/pi of the centers (for subobjects) |
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
maintainer-merge
label:t-algebra$ |
77/3 |
Mathlib.lean,Mathlib/Algebra/Algebra/NonUnitalSubalgebra.lean,Mathlib/Algebra/Algebra/Subalgebra/Pi.lean,Mathlib/Algebra/Algebra/Subalgebra/Prod.lean,Mathlib/Algebra/Group/Center.lean,Mathlib/Algebra/Ring/Subring/Basic.lean,Mathlib/Algebra/Ring/Subsemiring/Basic.lean,Mathlib/Algebra/Star/NonUnitalSubalgebra.lean,Mathlib/GroupTheory/Subgroup/Center.lean,Mathlib/GroupTheory/Submonoid/Center.lean,Mathlib/GroupTheory/Subsemigroup/Lemmas.lean,Mathlib/RingTheory/NonUnitalSubring/Basic.lean,Mathlib/RingTheory/NonUnitalSubsemiring/Basic.lean |
13 |
27 |
['SnirBroshi', 'github-actions', 'plp127', 'tb65536', 'themathqueen'] |
tb65536 assignee:tb65536 |
0-41709 11 hours ago |
1-65852 1 day ago |
1-81394 1 day |
| 39816 |
WenrongZou author:WenrongZou |
chore(MvPolynomial): rename a lemma using prime |
This PR renames a lemma by adding a prime. Many other lemmas in (mv)polynomial theory also use a prime in their names for the same reason — their primed versions should be rewritten in the `xxx_eq_ite` form.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
easy
|
13/10 |
Mathlib/Algebra/MvPolynomial/Basic.lean,Mathlib/RingTheory/MvPolynomial/IrreducibleQuadratic.lean,Mathlib/RingTheory/Smooth/IntegralClosure.lean,Mathlib/RingTheory/Spectrum/Prime/Polynomial.lean,Mathlib/RingTheory/TensorProduct/MvPolynomial.lean,scripts/nolints_prime_decls.txt |
6 |
11 |
['NoahW314', 'WenrongZou', 'github-actions', 'ocfnash'] |
nobody |
0-41505 11 hours ago |
0-41556 11 hours ago |
3-41412 3 days |
| 39941 |
mkaratarakis author:mkaratarakis |
feat(Data/List): add count lemmas for duplicate detection |
## Summary
Add general list count lemmas used in the Perron–Frobenius quiver-path development:
- `List.mem_tail_of_count_ge_two`
- `List.exists_pos_get_of_dropLast_count_ge_two`
Relocated from the PF-specific file per review feedback. Proofs use upstream `List.Duplicate` API and `grind` where appropriate (per @chenson2018).
Part of the Perron–Frobenius formalization (with @or4nge19).
## Test plan
- [x] `lake build Mathlib.Data.List.Count`
- [x] `lake build Mathlib.Combinatorics.Quiver.Path.PerronFrobenius` (on integration branch)
cc @or4nge19 for review |
t-data |
24/0 |
Mathlib/Data/List/Count.lean |
1 |
3 |
['chenson2018', 'github-actions', 'mkaratarakis'] |
nobody |
0-41432 11 hours ago |
2-23142 2 days ago |
2-23511 2 days |
| 39913 |
mkaratarakis author:mkaratarakis |
feat(Combinatorics/Quiver): periodicity and aperiodicity |
Add `Mathlib/Combinatorics/Quiver/Cyclic.lean`: cycle lengths, index of imprimitivity, and cyclic partitions for strongly connected quivers.
Imports only upstream mathlib (`Matrix.Irreducible.Defs`, etc.). Part of the Perron–Frobenius formalization (with @or4nge19).
---
---
[](https://gitpod.io/from-referrer/)
cc @or4nge19 for review |
t-combinatorics |
194/0 |
Mathlib.lean,Mathlib/Combinatorics/Quiver/Cyclic.lean |
2 |
2 |
['github-actions', 'or4nge19'] |
nobody |
0-41426 11 hours ago |
1-53282 1 day ago |
2-54447 2 days |
| 38859 |
SnirBroshi author:SnirBroshi |
feat(Order/CompleteLattice/Basic): tag `iSup_of_empty'` with `@[simp]` |
The theorem says `iSup f = sSup ∅` when the domain of `f` is empty, and dually `iInf f = sInf ∅`.
---
[](https://gitpod.io/from-referrer/)
|
t-order |
31/47 |
Mathlib/Algebra/Order/Archimedean/Real/Basic.lean,Mathlib/Analysis/Normed/Lp/lpSpace.lean,Mathlib/Analysis/Seminorm.lean,Mathlib/Data/ENat/Lattice.lean,Mathlib/Data/NNReal/Basic.lean,Mathlib/Data/Nat/Lattice.lean,Mathlib/Data/Set/Finite/Lattice.lean,Mathlib/LinearAlgebra/Eigenspace/Pi.lean,Mathlib/MeasureTheory/Constructions/BorelSpace/Order.lean,Mathlib/Order/CompleteLattice/Basic.lean,Mathlib/Order/ConditionallyCompleteLattice/Indexed.lean,Mathlib/Order/ConditionallyCompletePartialOrder/Indexed.lean,Mathlib/Order/Filter/Basic.lean,Mathlib/Order/Filter/Lift.lean |
14 |
2 |
['github-actions', 'mathlib-merge-conflicts'] |
nobody |
0-40989 11 hours ago |
5-46192 5 days ago |
25-79418 25 days |
| 38856 |
SnirBroshi author:SnirBroshi |
feat(Order/ConditionallyCompleteLattice/Indexed): `iSup_iSup_eq_{left/right}` for `ConditionallyCompleteLinearOrderBot` |
and `≤` versions for `ConditionallyCompleteLattice`.
---
[](https://gitpod.io/from-referrer/)
|
t-order |
32/9 |
Mathlib/Order/CompleteLattice/Basic.lean,Mathlib/Order/ConditionallyCompleteLattice/Indexed.lean |
2 |
1 |
['github-actions'] |
nobody |
0-40906 11 hours ago |
26-77388 26 days ago |
26-77157 26 days |
| 39952 |
vihdzp author:vihdzp |
feat: `IsBotOneClass (WithTop α)` |
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-order
easy
label:t-algebra$ |
4/0 |
Mathlib/Algebra/Order/Monoid/Unbundled/WithTop.lean |
1 |
1 |
['github-actions', 'plp127'] |
nobody |
0-40458 11 hours ago |
2-4409 2 days ago |
2-4178 2 days |
| 32692 |
WilliamCoram author:WilliamCoram |
feat: define multivariate restricted power series |
We define multivariate restricted power series over a normed ring R, and show the properties that they form a ring when R has the ultrametric property.
This work generalises my previous work in #26089 which will need to be refactored.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
t-number-theory
new-contributor
|
159/0 |
Mathlib.lean,Mathlib/Algebra/Order/Antidiag/Prod.lean,Mathlib/Algebra/Order/Antidiag/Tendsto.lean,Mathlib/RingTheory/MvPowerSeries/Restricted.lean |
4 |
51 |
['WilliamCoram', 'erdOne', 'github-actions', 'jcommelin', 'mathlib-merge-conflicts', 'mbkybky'] |
jcommelin assignee:jcommelin |
0-38977 10 hours ago |
10-37053 10 days ago |
53-12444 53 days |
| 36018 |
wwylele author:wwylele |
feat(LinearAlgebra/AffineSpace): parallel cross-section of a simplex |
This is preparing to calculate the volume of a simplex by integrating the cross-section created by shifting the base plane. Part of #37910.
---
- [ ] depends on: #38220
[](https://gitpod.io/from-referrer/)
|
t-algebra
large-import
label:t-algebra$ |
176/1 |
Mathlib/LinearAlgebra/AffineSpace/AffineSubspace/Shift.lean,Mathlib/LinearAlgebra/AffineSpace/Simplex/Basic.lean |
2 |
12 |
['alreadydone', 'copilot-pull-request-reviewer', 'github-actions', 'mathlib-bors', 'mathlib-dependent-issues', 'wwylele'] |
dagurtomas assignee:dagurtomas |
0-38249 10 hours ago |
2-3412 2 days ago |
40-715 40 days |
| 37577 |
SnirBroshi author:SnirBroshi |
feat(Combinatorics/SimpleGraph/Walk): upgrade subset theorems to sublist/prefix/suffix |
Upgrades theorems about `p.support ⊆ q.support` / `p.darts ⊆ q.darts` / `p.edges ⊆ q.edges` to `List.IsInfix`/`List.IsSuffix`/`List.Sublist`, which imply the subset versions.
Also adds `cycleBypass` sublist lemmas that were missing, and golfs `length_bypass_le` and `bypass_eq_self_of_length_le` using the new sublist theorems.
Co-authored-by: Iván Renison <85908989+IvanRenison@users.noreply.github.com>
---
Except for a couple of `cycleBypass` ones, I did not add such theorems where there was no subset theorem to begin with (e.g. `(p.take n).darts <+: p.darts`), as they are usually not worth stating since they're trivial and simp proves them.
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
maintainer-merge
|
182/113 |
Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Subgraph.lean,Mathlib/Combinatorics/SimpleGraph/Metric.lean,Mathlib/Combinatorics/SimpleGraph/Paths.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Decomp.lean,Mathlib/Combinatorics/SimpleGraph/Walk/Operations.lean |
7 |
7 |
['SnirBroshi', 'YaelDillies', 'b-mehta', 'github-actions'] |
b-mehta assignee:b-mehta |
0-37733 10 hours ago |
17-41695 17 days ago |
56-73841 56 days |
| 38557 |
SnirBroshi author:SnirBroshi |
feat(Order/Monotone/Defs): weaken `Preorder` to `LE`/`LT` |
`Monotone`/`Antitone`/`MonotoneOn`/`AntitoneOn` can use any `LE`,
and `StrictMono`/`StrictAnti`/`StrictMonoOn`/`StrictAntiOn` can use any `LT`.
This makes it necessary to add some explicit type params (e.g. `(α := α)`) in some places that use monotone-related theorems (e.g. `Function.monotone_eval`).
---
Currently `OrderEmbedding` and `OrderIso` can use `LE` but `OrderHom` requires `Preorder` because it's defined using `Monotone`. Generalizing `Monotone` and friends will let us fix this oddity. This follows other basic definitions such as `IsMax`/`CovBy`.
[](https://gitpod.io/from-referrer/)
|
t-order |
21/15 |
Mathlib/Analysis/BoxIntegral/Box/Basic.lean,Mathlib/Data/Finsupp/Lex.lean,Mathlib/Data/Finsupp/MonomialOrder/DegLex.lean,Mathlib/Order/Interval/Lex.lean,Mathlib/Order/Monotone/Defs.lean,Mathlib/RingTheory/MvPowerSeries/Trunc.lean,Mathlib/Topology/Order/MonotoneConvergence.lean |
7 |
2 |
['JovanGerb', 'github-actions'] |
nobody |
0-37711 10 hours ago |
33-3172 33 days ago |
33-5772 33 days |
| 39158 |
SnirBroshi author:SnirBroshi |
feat(LinearAlgebra/Matrix/Rank): generalize `Matrix.rank`/`LinearMap.rank` to semirings |
- Generalize `Matrix.rank` from `CommRing` to `CommSemiring`
- Generalize `LinearMap.rank` from `AddCommGroup`s over `Ring`s to `AddCommMonoid`s over `Semiring`s (which are the minimum requirements for `Module`)
- Many `Matrix.rank` theorems now require `StrongRankCondition` explicitly (which `CommRing` used to provide)
- `Matrix.cRank` theorems don't need commutativity
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
58/64 |
Mathlib/LinearAlgebra/Dimension/LinearMap.lean,Mathlib/LinearAlgebra/Matrix/Rank.lean |
2 |
1 |
['github-actions'] |
nobody |
0-37638 10 hours ago |
19-12236 19 days ago |
19-12005 19 days |
| 38349 |
SnirBroshi author:SnirBroshi |
chore(Combinatorics/SimpleGraph/Coloring/VertexColoring): rename to `Vertex.lean` |
After #37525 moved `Coloring.lean` to `Coloring/VertexColoring.lean`, a [Zulip](https://leanprover.zulipchat.com/#narrow/channel/252551-graph-theory/topic/Coloring.20module.20names/with/583281500) poll decided to avoid duplicating the word "Coloring", so this renames `Coloring/VertexColoring.lean` to `Coloring/Vertex.lean`.
---
I planned to make this move in #33313 but it isn't moving along, so I think it's best to split the renaming.
#37546 adds module deprecation
[](https://gitpod.io/from-referrer/)
|
file-removed
t-combinatorics
|
6/6 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/Constructions.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/Vertex.lean,Mathlib/Combinatorics/SimpleGraph/CompleteMultipartite.lean,Mathlib/Combinatorics/SimpleGraph/Partition.lean,Mathlib/Combinatorics/SimpleGraph/Sum.lean |
7 |
3 |
['github-actions', 'mathlib-merge-conflicts'] |
nobody |
0-37592 10 hours ago |
5-45334 5 days ago |
37-18645 37 days |
| 40019 |
grunweg author:grunweg |
chore: golf using fun_prop |
Partially enabled through #35683.
---
[](https://gitpod.io/from-referrer/)
|
|
14/30 |
Mathlib/Analysis/Convex/Contractible.lean,Mathlib/Condensed/Discrete/LocallyConstant.lean,Mathlib/Condensed/Light/Sequence.lean,Mathlib/MeasureTheory/Constructions/Polish/Basic.lean,Mathlib/MeasureTheory/Function/SpecialFunctions/Basic.lean |
5 |
1 |
['github-actions'] |
nobody |
0-35464 9 hours ago |
0-35533 9 hours ago |
0-35302 9 hours |
| 26394 |
winstonyin author:winstonyin |
feat: existence of local flows on manifolds |
This PR continues the work from #21777.
Original PR: https://github.com/leanprover-community/mathlib4/pull/21777
Transfer the existence theorem of local flows on vector spaces to manifolds. The precise statement is:
> If a vector field `v` on a manifold `M` is continuously differentiable at an interior point `x₀`, then for a given `t₀` there exists a neighbourhood `u` of `x₀`, a positive `ε`, and `γ : M → ℝ → M` such that `γ x` is an integral curve of `v` on `(t₀ - ε, t₀ + ε)` for all `x ∈ u`.
This is powerful because all curves `γ x` (each with initial condition `x ∈ u`) share the same existence time interval `(t₀ - ε, t₀ + ε)`, rather than each curve having its own `ε`. This will allow us to show that $C^1$ vector fields on compact manifolds always have global integral curves / global flows.
Any suggestions to shorten the proof or split out useful lemmas are welcome!
- [x] depends on: #26392
---
[](https://gitpod.io/from-referrer/)
|
t-differential-geometry |
138/61 |
Mathlib/Analysis/ODE/PicardLindelof.lean,Mathlib/Geometry/Manifold/IntegralCurve/ExistUnique.lean,Mathlib/Order/Filter/Prod.lean |
3 |
11 |
['github-actions', 'grunweg', 'leanprover-community-bot-assistant', 'mathlib-merge-conflicts', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'ocfnash', 'winstonyin'] |
ocfnash assignee:ocfnash |
0-34930 9 hours ago |
0-35014 9 hours ago |
22-15544 22 days |
| 39714 |
tb65536 author:tb65536 |
feat(RingTheory/Localization/AtPrime/Basic): add variants of `localAlgHom` and `localAlgEquiv` |
This PR adds variants of `localAlgHom` and `localAlgEquiv` where the base ring is also localized.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
t-algebra
label:t-algebra$ |
39/7 |
Mathlib/RingTheory/Localization/AtPrime/Basic.lean,Mathlib/RingTheory/Localization/Basic.lean |
2 |
2 |
['github-actions', 'tb65536'] |
nobody |
0-33940 9 hours ago |
7-33486 7 days ago |
7-33257 7 days |
| 40022 |
chenson2018 author:chenson2018 |
chore(Algebra): refactor proofs where `grind?` fails |
These are sources of technical debt as now reported in the [weekly linting report](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Weekly.20linting.20log/with/544658968). The idea is that a successful grind proof can fail to report the theorems it used via grind?, which means that if these proofs break across toolchains that it becomes significantly harder to repair.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
16/6 |
Mathlib/Algebra/Group/Defs.lean,Mathlib/Algebra/Notation/Support.lean,Mathlib/Algebra/Order/BigOperators/Group/Finset.lean,Mathlib/Algebra/Order/Field/Basic.lean,Mathlib/Algebra/Order/Ring/StandardPart.lean,Mathlib/Algebra/Polynomial/Degree/Lemmas.lean |
6 |
1 |
['github-actions'] |
nobody |
0-33655 9 hours ago |
0-33741 9 hours ago |
0-33510 9 hours |
| 40023 |
chenson2018 author:chenson2018 |
chore(AlgebraicTopology): refactor proofs where `grind?` fails |
These are sources of technical debt as now reported in the [weekly linting report](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Weekly.20linting.20log/with/544658968). The idea is that a successful grind proof can fail to report the theorems it used via grind?, which means that if these proofs break across toolchains that it becomes significantly harder to repair.
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-topology |
11/5 |
Mathlib/AlgebraicTopology/SimplexCategory/DeltaZeroIter.lean,Mathlib/AlgebraicTopology/SimplexCategory/GeneratorsRelations/NormalForms.lean,Mathlib/AlgebraicTopology/SimplicialSet/NonDegenerateSimplices.lean,Mathlib/AlgebraicTopology/SimplicialSet/NonDegenerateSimplicesSubcomplex.lean |
4 |
1 |
['github-actions'] |
nobody |
0-33204 9 hours ago |
0-33301 9 hours ago |
0-33070 9 hours |
| 40020 |
kbuzzard author:kbuzzard |
wip |
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
38/27 |
Mathlib/Algebra/Group/Pi/Basic.lean |
1 |
4 |
['github-actions', 'kbuzzard', 'leanprover-radar'] |
nobody |
0-33055 9 hours ago |
0-33899 9 hours ago |
0-33668 9 hours |
| 40024 |
ADedecker author:ADedecker |
chore: rename Pi.monoidHom to MonoidHom.pi |
Zulip discussion: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Pi.2EfooHom.20or.20FooHom.2Epi/near/598538630
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
45/21 |
Mathlib/Algebra/Category/Grp/Yoneda.lean,Mathlib/Algebra/Category/MonCat/Yoneda.lean,Mathlib/Algebra/Group/Pi/Lemmas.lean,Mathlib/Algebra/Ring/Pi.lean,Mathlib/LinearAlgebra/Pi.lean |
5 |
1 |
['github-actions'] |
nobody |
0-32742 9 hours ago |
0-32830 9 hours ago |
0-32599 9 hours |
| 39787 |
Hagb author:Hagb |
feat(Order/WellQuasiOrder): `WellQuasiOrdered` if onto homomorphous from a `WellQuasiOrdered` relation |
It is used in #39788 for proof of well foundedness of `MonomialOrder` when the index type is finite.
The hypotheses can be further weaken once #38557 is merged.
---
[](https://gitpod.io/from-referrer/)
|
t-order
easy
|
16/0 |
Mathlib/Order/WellQuasiOrder.lean |
1 |
3 |
['Hagb', 'github-actions', 'plp127'] |
nobody |
0-32234 8 hours ago |
5-18310 5 days ago |
5-18079 5 days |
| 39873 |
mkaratarakis author:mkaratarakis |
feat(RingTheory/IntegralClosure): add IsIntegral helpers for casts |
Add `IsIntegral.Cast` and `IsIntegral.Nat`, stating that integer and natural
literals are integral over `ℤ` in a field.
---
[](https://gitpod.io/from-referrer/) |
t-ring-theory |
7/0 |
Mathlib/RingTheory/IntegralClosure/Algebra/Basic.lean |
1 |
8 |
['github-actions', 'mkaratarakis', 'tb65536'] |
nobody |
0-31762 8 hours ago |
2-62372 2 days ago |
2-68657 2 days |
| 40016 |
xhalo32 author:xhalo32 |
feat(InfiniteSum): add hasProd_ite_eq' and tprod_ite_eq' |
Adds `eq'` variants that mirror those in `Mathlib/Algebra/BigOperators/Group/Finset/Piecewise.lean` and `Mathlib/Algebra/BigOperators/Finsupp/Basic.lean`.
For proof of their usefulness, these summability lemmas about indicator functions are now straight-forward:
```lean
theorem hasSum_indicator_singleton_const [CommMonoid α] [TopologicalSpace α] [TopologicalSpace β] [AddCommMonoid β]
{x : α} {f : α → β} (L := unconditional α) [L.LeAtTop]
: HasSum (fun y => Set.indicator {y} f x) (f x) L
:= by
classical
exact hasSum_ite_eq' x (f x) L
theorem summable_indicator_singleton_const [CommMonoid α] [TopologicalSpace α] [TopologicalSpace β] [AddCommMonoid β]
{x : α} {f : α → β} (L := unconditional α) [L.LeAtTop]
: Summable (fun y => Set.indicator {y} f x) L
:= ⟨_, hasSum_indicator_singleton_const _⟩
```
We are also depending on these proofs in [Polya-lean](https://github.com/alma-n/polya-lean).
Update: changed `convert` to `convert!`.
---
[](https://gitpod.io/from-referrer/)
|
t-topology
new-contributor
|
14/0 |
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean |
1 |
3 |
['github-actions', 'xhalo32'] |
nobody |
0-31103 8 hours ago |
0-34387 9 hours ago |
0-38586 10 hours |
| 40015 |
SnirBroshi author:SnirBroshi |
chore: replace some `omega`s |
None of these had any noticable slowdown.
---
Is it time to add `omega` to the technical debt counters? There are ~250 left.
[](https://gitpod.io/from-referrer/)
|
tech debt |
7/7 |
Mathlib/Combinatorics/SimpleGraph/Walk/Subwalks.lean,Mathlib/Data/Finset/Powerset.lean,Mathlib/Data/Int/Interval.lean,Mathlib/Data/List/Defs.lean,Mathlib/Data/List/Infix.lean |
5 |
6 |
['SnirBroshi', 'chenson2018', 'github-actions', 'grunweg'] |
nobody |
0-30084 8 hours ago |
0-30086 8 hours ago |
0-34237 9 hours |
| 39189 |
tb65536 author:tb65536 |
feat(RingTheory/RamificationInertia/Basic): ramification-inertia formula for finite flat extensions |
This PR proves the ramification-inertia formula for finite flat extensions.
---
- [x] depends on: #38825
- [x] depends on: #39094
- [x] depends on: #39196
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
t-algebra
label:t-algebra$ |
114/3 |
Mathlib.lean,Mathlib/FieldTheory/Galois/IsGaloisGroup.lean,Mathlib/RingTheory/LocalRing/ResidueField/Fiber.lean,Mathlib/RingTheory/RamificationInertia/Basic.lean |
4 |
2 |
['github-actions', 'mathlib-dependent-issues'] |
nobody |
0-30036 8 hours ago |
0-30036 8 hours ago |
1-27757 1 day |
| 40025 |
artie2000 author:artie2000 |
chore(Data/SetLike/Basic): generalise instance |
* Generalise the standard `IsConcreteLE` instance from `PartialOrder.ofSetLike` to `LE.ofSetLike`
---
[](https://gitpod.io/from-referrer/)
|
t-data |
8/4 |
Mathlib/Data/SetLike/Basic.lean |
1 |
2 |
['github-actions'] |
nobody |
0-29509 8 hours ago |
0-29734 8 hours ago |
0-29503 8 hours |
| 33143 |
wwylele author:wwylele |
feat(PowerSeries): pentagonal number theorem |
The proof is split in two files: `Mathlib/Topology/Algebra/InfiniteSum/Pentagonal.lean` for the algebraic part, and `Mathlib/RingTheory/PowerSeries/Pentagonal.lean` for the summability part. In the near future, I also plan to prove the real/complex version that branches off from the algebraic part.
---
- [x] depends on: #30436
- [x] depends on: #38179
[](https://gitpod.io/from-referrer/)
|
t-algebra
large-import
label:t-algebra$ |
361/6 |
Mathlib.lean,Mathlib/Combinatorics/Enumerative/Pentagonal.lean,Mathlib/RingTheory/PowerSeries/Pentagonal.lean,Mathlib/Topology/Algebra/InfiniteSum/Pentagonal.lean,docs/1000.yaml |
5 |
59 |
['copilot-pull-request-reviewer', 'github-actions', 'jcommelin', 'mathlib-dependent-issues', 'tb65536', 'urkud', 'vihdzp', 'wwylele'] |
mattrobball assignee:mattrobball |
0-29119 8 hours ago |
28-3967 28 days ago |
138-15593 138 days |
| 34908 |
CoolRmal author:CoolRmal |
feat(GroupTheory): a characteristic subgroup of a characteristic subgroup is characteristic |
The main theorem proved in this PR is `characteristic_of_characteristic_of_characteristic`. If says that if `K` is a characteristic subgroup of a characteristic subgroup `H` of `G`, then `K` is a characteristic subgroup of `G`.
Created with the help of Codex.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-group-theory
LLM-generated
label:t-algebra$ |
25/0 |
Mathlib/Algebra/Group/Subgroup/Basic.lean |
1 |
22 |
['CoolRmal', 'github-actions', 'robin-carlier', 'tb65536'] |
mattrobball assignee:mattrobball |
0-28050 7 hours ago |
0-28050 7 hours ago |
10-76702 10 days |
| 39904 |
wwylele author:wwylele |
refactor(Analysis/Meromorphic): generalize 𝕜 → 𝕜 to 𝕜 → 𝕜' for order lemma when possible |
I don't have a real use for this, but this is the style that Meromorphic/Basic.lean follows, so let's unify them.
---
I unfortunately had to duplicate the proof for `meromorphicOrderAt_mul` from `meromorphicOrderAt_smul`. They are almost the same, but I don't find a good way to unify them.
[](https://gitpod.io/from-referrer/)
|
t-analysis |
38/22 |
Mathlib/Analysis/Meromorphic/Order.lean |
1 |
1 |
['github-actions'] |
nobody |
0-27893 7 hours ago |
3-2635 3 days ago |
3-2404 3 days |
| 39831 |
wwylele author:wwylele |
feat(Topology): a preconnected set is discrete iff is subsingleton |
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
9/0 |
Mathlib/Topology/Connected/TotallyDisconnected.lean |
1 |
1 |
['github-actions'] |
nobody |
0-27881 7 hours ago |
4-38803 4 days ago |
4-38572 4 days |
| 39680 |
grunweg author:grunweg |
feat(CI): validate PR titles more strictly |
- lint extraneous spaces (and any tabs)
- check that PR scopes are well-formed
- also extract the PR subject, and check that it does not end in a period, and starts in lower-case
- linter about strange Unicode characters (anything not allowed by the Unicode linter)
Continuation of #34518: this covers the remaining checks of #16303.
(This does not check that the subject is in imperative, present tense.)
---
[](https://gitpod.io/from-referrer/)
|
t-linter
maintainer-merge
|
196/37 |
Mathlib/Tactic/Linter/ValidatePRTitle.lean,MathlibTest/ValidatePRTitle.lean |
2 |
18 |
['SnirBroshi', 'github-actions', 'grunweg', 'joneugster'] |
JovanGerb assignee:JovanGerb |
0-26762 7 hours ago |
0-27958 7 hours ago |
7-76757 7 days |
| 39136 |
vihdzp author:vihdzp |
feat: more results on `Order.enum` |
Most importantly, we prove that the enumerator function of a (cofinal) set is normal iff the set is closed (under non-empty suprema).
---
- [x] depends on: #38362
- [x] depends on: #39137
[](https://gitpod.io/from-referrer/)
|
t-set-theory
t-order
maintainer-merge
|
90/7 |
Mathlib/Order/Cofinal.lean,Mathlib/SetTheory/Cardinal/Cofinality/Club.lean,Mathlib/SetTheory/Cardinal/Cofinality/Enum.lean,Mathlib/SetTheory/Ordinal/Topology.lean |
4 |
7 |
['YaelDillies', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'vihdzp'] |
nobody |
0-25229 7 hours ago |
1-20160 1 day ago |
1-70243 1 day |
| 39833 |
wwylele author:wwylele |
feat(Analysis/Meromorphic): const_smul lemma |
This allows more general scalar type than the existing `smul` ones
---
[](https://gitpod.io/from-referrer/)
|
t-analysis |
14/0 |
Mathlib/Analysis/Meromorphic/Basic.lean |
1 |
1 |
['github-actions'] |
nobody |
0-24101 6 hours ago |
0-24179 6 hours ago |
4-35602 4 days |
| 37415 |
vasnesterov author:vasnesterov |
feat(Tactic/ComputeAsymptotics/Multiseries): compute limits of `Monomial`s |
Prove
* `UnitMonomial.logToFun_isEquivalent_of_nonzero_head`: `log m.toFun` is asymptotically equivalent
to its first summand - `m[0] • log basis[0]` if `m[0] ≠ 0`. Using this theorem we can prove that
the asymptotic behavior of a monomial is determined by its first non-zero exponent.
* `toFun_tendsto_top_of_FirstNonzeroIsPos` and its variants: used to infer the limit of
`t.toFun` from `FirstNonzeroIsPos`/`FirstNonzeroIsNeg`/`AllZero`.
* `IsLittleO_of_lt_exps` and its variants: used to asymptotically compare two monomials.
---
- [x] depends on: #37411
This is a part of the `compute_asymptotics` tactic (#28291).
[](https://gitpod.io/from-referrer/)
|
t-meta
maintainer-merge
|
378/1 |
Mathlib/Tactic/ComputeAsymptotics/Multiseries/Basis.lean,Mathlib/Tactic/ComputeAsymptotics/Multiseries/Monomial/Basic.lean |
2 |
16 |
['github-actions', 'joneugster', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
joneugster assignee:joneugster |
0-22750 6 hours ago |
0-51870 14 hours ago |
14-37596 14 days |
| 39703 |
YaelDillies author:YaelDillies |
chore: create a `Basic` top folder |
Move a select few folders from `Logic` to a new `Basic` folder.
The goal is to finally move the material misplaced in the `Data` and `Logic` folder and to clarify the various expectations of each folder. Ultimately:
* the `Basic` folder will be about basic predicates on types and basic mathematical types not fitting in any other folder;
* the `Data` folder will be about data structures, instead of the current mix of data structures and basic mathematical types not fitting in any other folder;
* the `Logic` folder will be about advanced logic results not fitting in either `ModelTheory` or `SetTheory`, instead of the current mix of basic predicates on types and advanced logic results.
Many more files (~1000) could be moved, so I will do it in several PRs. Not all files should move to `Basic`. Some files should go to `Algebra.Order` instead (eg `Data.Nat.Lattice`) and some should be straight out deprecated (eg `Data.Analysis`).
[Zulip discussion](https://leanprover.zulipchat.com/#narrow/channel/345428-mathlib-reviewers/topic/Basic.20folder/with/597151406)
---
This PR stems from discussions at the MI retreat 2026.
[](https://gitpod.io/from-referrer/)
|
file-removed
t-data
maintainer-merge
|
148/96 |
Counterexamples/Girard.lean,Mathlib.lean,Mathlib/Algebra/CharZero/Defs.lean,Mathlib/Algebra/Group/Irreducible/Defs.lean,Mathlib/Algebra/Group/Nat/Units.lean,Mathlib/Algebra/Group/Pi/Basic.lean,Mathlib/Algebra/Group/Units/Basic.lean,Mathlib/Algebra/Group/WithOne/Defs.lean,Mathlib/Algebra/GroupWithZero/Basic.lean,Mathlib/Algebra/GroupWithZero/Defs.lean,Mathlib/Algebra/Module/Presentation/Free.lean,Mathlib/Algebra/Module/Projective.lean,Mathlib/Algebra/NeZero.lean,Mathlib/Basic/Denumerable.lean,Mathlib/Basic/ExistsUnique.lean,Mathlib/Basic/IsEmpty.lean,Mathlib/Basic/IsEmpty/Basic.lean,Mathlib/Basic/IsEmpty/Defs.lean,Mathlib/Basic/Logic/Basic.lean,Mathlib/Basic/Logic/Lemmas.lean,Mathlib/Basic/Nonempty.lean,Mathlib/Basic/Nontrivial/Basic.lean,Mathlib/Basic/Nontrivial/Defs.lean,Mathlib/Basic/README.md,Mathlib/Basic/Unique.lean,Mathlib/Basic/UnivLE.lean,Mathlib/CategoryTheory/EssentiallySmall.lean,Mathlib/CategoryTheory/Limits/Types/Colimits.lean,Mathlib/CategoryTheory/Limits/Types/Limits.lean,Mathlib/CategoryTheory/UnivLE.lean,Mathlib/Combinatorics/Quiver/Path.lean,Mathlib/Computability/Primrec/Basic.lean,Mathlib/Data/Bool/Basic.lean,Mathlib/Data/FunLike/Basic.lean,Mathlib/Data/List/Basic.lean,Mathlib/Data/List/GetD.lean,Mathlib/Data/Nat/Basic.lean,Mathlib/Data/Nat/MaxPowDiv.lean,Mathlib/Data/Option/Basic.lean,Mathlib/Data/Quot.lean,Mathlib/Data/README.md,Mathlib/Data/Rat/Denumerable.lean,Mathlib/Data/TwoPointing.lean,Mathlib/Lean/Meta/CongrTheorems.lean,Mathlib/LinearAlgebra/Matrix/Defs.lean,Mathlib/Logic/Equiv/Defs.lean,Mathlib/Logic/Equiv/List.lean,Mathlib/Logic/Function/Basic.lean,Mathlib/Logic/README.md,Mathlib/Order/OrderIsoNat.lean,Mathlib/Order/RelClasses.lean,Mathlib/Order/WithBot.lean,Mathlib/RingTheory/Coprime/Basic.lean,Mathlib/SetTheory/Cardinal/Basic.lean,Mathlib/SetTheory/Cardinal/UnivLE.lean,Mathlib/SetTheory/ZFC/Rank.lean,Mathlib/Tactic/CancelDenoms/Core.lean,Mathlib/Tactic/CongrExclamation.lean,Mathlib/Tactic/ITauto.lean,Mathlib/Tactic/Linter/DirectoryDependency.lean,Mathlib/Tactic/Nontriviality/Core.lean,Mathlib/Tactic/Push.lean,Mathlib/Tactic/Subsingleton.lean,Mathlib/Tactic/Tauto.lean,Mathlib/Testing/Plausible/Testable.lean,Mathlib/Topology/Order/UpperLowerSetTopology.lean,MathlibTest/Linter/PrivateModule/ImportOnly.lean,scripts/autolabel.lean,scripts/noshake.json |
69 |
25 |
['SnirBroshi', 'YaelDillies', 'github-actions', 'grunweg', 'joneugster', 'mathlib-merge-conflicts', 'themathqueen'] |
joneugster assignee:joneugster |
0-22369 6 hours ago |
0-24203 6 hours ago |
3-48174 3 days |
| 39988 |
grunweg author:grunweg |
refactor(Tactic/Translate): document name translation a bit more |
I found the code a bit hard to read: the following commits each improve the code slightly.
Also add a test exercising the "name matches the auto-generated name" code path.
#39962 will tweak the naming algorithm slightly.
---
[](https://gitpod.io/from-referrer/)
|
t-meta |
35/20 |
Mathlib/Tactic/Translate/Core.lean,Mathlib/Tactic/Translate/TagUnfoldBoundary.lean,MathlibTest/Attribute/ToAdditive/Basic.lean |
3 |
8 |
['github-actions', 'grunweg', 'joneugster', 'thorimur'] |
joneugster assignee:joneugster |
0-22363 6 hours ago |
0-22363 6 hours ago |
1-10883 1 day |
| 37342 |
vasnesterov author:vasnesterov |
feat(Tactic/ComputeAsymptotics/Multiseries): non-primitive corecursion for Seq: more `FriendlyOperation` API |
This is a continuation of #35072.
This PR adds more API about friendly operations:
* `FriendlyOperation.coind`: a coinductive principle for proving that operation is friendly
* `FriendlyOperationClass.eq_of_bisim`: a generalisation of `Seq.eq_of_bisim'` for proving two sequences are equal.
---
- [x] depends on: #35072
This is a part of the `compute_asymptotics` tactic (#28291).
[](https://gitpod.io/from-referrer/)
|
t-data
t-meta
maintainer-merge
|
160/0 |
Mathlib/Tactic/ComputeAsymptotics/Multiseries/Corecursion.lean |
1 |
7 |
['github-actions', 'joneugster', 'mathlib-dependent-issues'] |
joneugster assignee:joneugster |
0-22236 6 hours ago |
0-52975 14 hours ago |
29-40587 29 days |
| 40028 |
marcelolynch author:marcelolynch |
chore(ci): tweaks to Lake cache shadow workflow |
This PR tweaks the Lake cache shadow workflow (#39402) with some improvements
- Bump actions (removes some warnings)
- Report new content uploaded per run. This is surfaced as a new Zulip line, e.g. `📦 new content uploaded: 47MiB across 312 new artifact(s) vs rev a1b2c3d4e5f6 (distance: 84 commits)`.
- Route the Zulip summary to `nightly-testing-mathlib` instead of `nightly-testing`. |
CI |
42/4 |
.github/workflows/lake_cache_shadow.yml |
1 |
1 |
['github-actions'] |
nobody |
0-21608 6 hours ago |
0-21745 5 hours ago |
0-21514 5 hours |
| 39875 |
mkaratarakis author:mkaratarakis |
refactor(NumberField/House): expose Siegel lemma infrastructure |
Expose Siegel's lemma infrastructure in `NumberField.House`: rename the private
basis-matrix bound to `basisMatrixInvSupNorm`, make `house` reducible, and
adjust `exists_ne_zero_int_vec_house_le`.
---
[](https://gitpod.io/from-referrer/) |
|
59/48 |
Mathlib/NumberTheory/NumberField/House.lean |
1 |
4 |
['github-actions', 'mkaratarakis', 'tb65536'] |
nobody |
0-21267 5 hours ago |
3-24942 3 days ago |
3-28438 3 days |
| 39872 |
mkaratarakis author:mkaratarakis |
feat(RingTheory/Algebraic): add natDenominator API |
Add `AlgebraicDenominator.denominator` and `AlgebraicDenominator.natDenominator`,
characterizing denominators of algebraic elements as generators of a colon ideal and,
over `ℤ`, their absolute value as a natural-number denominator.
Part of the Gelfond–Schneider formalization; see #39873, #39875, and #39874.
---
[](https://gitpod.io/from-referrer/)
cc @tb65536 |
t-ring-theory |
68/0 |
Mathlib.lean,Mathlib/RingTheory/Algebraic/NatDenominator.lean |
2 |
1 |
['github-actions'] |
nobody |
0-21225 5 hours ago |
3-42212 3 days ago |
3-41981 3 days |
| 39984 |
grunweg author:grunweg |
chore(Data): move some files to better locations |
Move a number of files in `Data` to clearly better locations.
See individual commit messages for details.
---
- [x] depends on: #39976
[](https://gitpod.io/from-referrer/)
|
file-removed
tech debt
|
30/30 |
Counterexamples/HomogeneousPrimeNotPrime.lean,Mathlib.lean,Mathlib/Algebra/Group/ConjFinite.lean,Mathlib/Algebra/Group/Subgroup/Finite.lean,Mathlib/Algebra/GroupWithZero/Units/Fintype.lean,Mathlib/Algebra/Lie/SerreConstruction.lean,Mathlib/Analysis/Calculus/ContDiff/FaaDiBruno.lean,Mathlib/Analysis/Real/Cardinality.lean,Mathlib/CategoryTheory/Galois/Basic.lean,Mathlib/Combinatorics/SimpleGraph/VertexCover.lean,Mathlib/Data/Set/PowersetCard.lean,Mathlib/Data/ZMod/Basic.lean,Mathlib/GroupTheory/Index.lean,Mathlib/GroupTheory/SpecificGroups/Alternating.lean,Mathlib/LinearAlgebra/Matrix/Action.lean,Mathlib/LinearAlgebra/Matrix/Bilinear.lean,Mathlib/LinearAlgebra/Matrix/Cartan.lean,Mathlib/LinearAlgebra/Matrix/DualNumber.lean,Mathlib/LinearAlgebra/Matrix/Invertible.lean,Mathlib/LinearAlgebra/Matrix/NonsingularInverse.lean,Mathlib/LinearAlgebra/Matrix/SchurComplement.lean,Mathlib/LinearAlgebra/Matrix/SpecialLinearGroup.lean,Mathlib/LinearAlgebra/Projectivization/Cardinality.lean,Mathlib/NumberTheory/MulChar/Basic.lean,Mathlib/RingTheory/SimpleModule/Basic.lean,Mathlib/SetTheory/Cardinal/Embedding.lean,Mathlib/SetTheory/Cardinal/NatCard.lean,Mathlib/SetTheory/Cardinal/Rat.lean,Mathlib/Topology/Compactification/OnePoint/ProjectiveLine.lean,scripts/noshake.json |
30 |
3 |
['github-actions', 'mathlib-dependent-issues'] |
nobody |
0-20653 5 hours ago |
0-22629 6 hours ago |
0-22454 6 hours |
| 37295 |
wwylele author:wwylele |
feat(Analysis/InnerProductSpace): generalized determinant of a rectangle matrix / linear map |
This is the volume factor of a linear map
---
I have encountered the expression `sqrt(det(T' * T))` a few times in various places but it doesn't look like it has a standard name and entry in mathlib, so this adds it.
Zulip thread [#Is there code for X? > (norm of) "determinant" of map between inner product spaces](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/.28norm.20of.29.20.22determinant.22.20of.20map.20between.20inner.20product.20spaces/with/581776873)
One motivation to define this is to state volume formula under transformations. From *Measure theory and fine properties of functions*:
- Lemma 3.1: for linear map $L : \mathbb{R}^n \to \mathbb{R}^m$, we have $\mathcal{H}^n(L(A)) = [ L ] \mathcal{L}^n(A)$. This is proved in this PR at `euclideanHausdorffMeasure_image_eq_normDet_mul_volume`
- Theorem 3.8, for (not necessarily linear) $f : \mathbb{R}^n \to \mathbb{R}^m$ ($n \le m$) and $\mathcal{L}^n$-measurable set $A \subset \mathbb{R}^n$, we have $\int_A J f dx = \int_{\mathbb{R}^m} \mathcal{H}^0(A \cap f\^{-1}\{y\}) d\mathcal{H}^n(y)$, where $J f$ is the `normDet` of the rectangular Jacobian matrix
AI usage disclosure: AI was used in the following parts
- searching for related literature for an appropriate name
- generate draft proofs for some lemma to verify their correctness, though the final code has been completely rewritten by me.
- [ ] depends on: #37918
[](https://gitpod.io/from-referrer/)
|
t-analysis
maintainer-merge
|
480/0 |
Mathlib.lean,Mathlib/Analysis/InnerProductSpace/Adjoint.lean,Mathlib/Analysis/InnerProductSpace/NormDet.lean,docs/references.bib |
4 |
19 |
['copilot-pull-request-reviewer', 'github-actions', 'j-loreaux', 'mathlib-dependent-issues', 'themathqueen', 'wwylele'] |
faenuccio and themathqueen assignee:themathqueen assignee:faenuccio |
0-20364 5 hours ago |
25-24420 25 days ago |
59-12351 59 days |
| 39996 |
RuthP628 author:RuthP628 |
feat(ModelTheory/Semantics): add simp theorems similar to Sentence.realize_not |
Add simp theorems Sentence.realize_bot, Sentence.realize_top, Sentence.realize_inf, Sentence.realize_sup, Sentence.realize_imp and Sentence.realize_iff in the style of Sentence.realize_not as consequences of the corresponding theorems for formulas. |
t-logic
new-contributor
|
31/1 |
Mathlib/ModelTheory/Semantics.lean |
1 |
10 |
['RuthP628', 'b-mehta', 'github-actions', 'plp127'] |
nobody |
0-17558 4 hours ago |
0-44564 12 hours ago |
0-51572 14 hours |
| 40029 |
vasnesterov author:vasnesterov |
feat(Analysis/Analytic): alternating geometric series |
* Define `geometricAlternatingSeries`: `1 - x + x ^ 2 - ...` as a `FormalMultilinearSeries`.
* Prove the same lemmas as for existing `formalMultilinearSeries_geometric`.
* Move the "Composition with a linear map" section above as it's needed to directly translate the results about `formalMultilinearSeries_geometric` to results about `geometricAlternatingSeries`.
---
[](https://gitpod.io/from-referrer/)
|
t-analysis |
132/65 |
Mathlib/Analysis/Analytic/Constructions.lean |
1 |
1 |
['github-actions'] |
nobody |
0-16510 4 hours ago |
0-16597 4 hours ago |
0-16366 4 hours |
| 39972 |
tb65536 author:tb65536 |
feat(GroupTheory/Torsion): the free rank of an abelian group |
This PR defines the rank of the free part of an abelian group.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-group-theory
label:t-algebra$ |
29/0 |
Mathlib/GroupTheory/Torsion.lean |
1 |
7 |
['github-actions', 'plp127', 'riccardobrasca', 'tb65536'] |
riccardobrasca assignee:riccardobrasca |
0-11622 3 hours ago |
1-44242 1 day ago |
1-44013 1 day |
| 40032 |
ADedecker author:ADedecker |
feat: define MonoidHom.piMap |
---
[](https://gitpod.io/from-referrer/)
|
t-algebra label:t-algebra$ |
46/22 |
Mathlib/Algebra/Group/Pi/Lemmas.lean |
1 |
1 |
['github-actions'] |
nobody |
0-11063 3 hours ago |
0-11147 3 hours ago |
0-10916 3 hours |
| 40033 |
JJYYY-JJY author:JJYYY-JJY |
chore: remove flexible linter suppressions |
This PR removes two local `linter.flexible` suppressions by replacing compact `simp; infer_instance` with explicit proofs.
Changed files:
- `Mathlib/Dynamics/TopologicalEntropy/DynamicalEntourage.lean`
- `Mathlib/Topology/UniformSpace/Ultra/Constructions.lean`
Tested with:
`lake build`
---
[](https://gitpod.io/from-referrer/)
|
new-contributor |
20/8 |
Mathlib/Dynamics/TopologicalEntropy/DynamicalEntourage.lean,Mathlib/Topology/UniformSpace/Ultra/Constructions.lean |
2 |
2 |
['github-actions'] |
nobody |
0-11058 3 hours ago |
0-11135 3 hours ago |
0-10904 3 hours |
| 40011 |
SnirBroshi author:SnirBroshi |
feat(Algebra/Group/Subgroup/Pointwise): iSup of normal subgroups is normal |
This is a generalization of `sup_normal`, which is for the supremum of two subgroups.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
t-group-theory
label:t-algebra$ |
29/0 |
Mathlib/Algebra/Group/Subgroup/Basic.lean,Mathlib/Algebra/Group/Subgroup/Pointwise.lean |
2 |
2 |
['github-actions', 'tb65536'] |
nobody |
0-10926 3 hours ago |
0-46604 12 hours ago |
0-46373 12 hours |
| 39339 |
marcelolynch author:marcelolynch |
feat(ci): add !downstream-check PR-validation workflow |
This PR adds a comment-triggered workflow that lets maintainers validate a mathlib4 PR
against curated downstream Lean projects. A user comments
!downstream-check FLT, Toric --merge-branch, carleson@v1.2.3
on a PR and the workflow:
* gates the commenter on `author_association ∈ {OWNER, MEMBER, COLLABORATOR}`,
* checks out `leanprover-community/mathlib-ci` via the existing `get-mathlib-ci`
composite action and runs `./ci-tools/.github/actions/check-downstream-validate`
on the directive (parses the grammar, resolves the PR's `merge_commit_sha`,
and POSTs a user-facing PR comment if the syntax is wrong),
* mints an App token and dispatches `mathlib-pr-validation.yml` in
`leanprover-community/downstream-reports`,
* runs `./ci-tools/.github/actions/check-downstream-ack` to post an
acknowledgement comment on the PR.
Grammar (each comma-separated entry):
[@] [--merge-branch]
* `` — inventory short name (e.g. `FLT`) or GitHub `owner/repo`
slug. Resolved by the dispatched workflow.
* `@` — optional. Any git refspec for the downstream's checkout.
* `--merge-branch` — optional, per entry. Flips that entry from the default
LKG mode (cherry-pick PR onto the downstream's last-known-good mathlib) to
merge mode (build against the PR's merge tree).
Grammar errors leave a comment on the PR addressing the requester, quoting
the parser's error + a usage hint, so a typo doesn't bury the diagnosis in
the workflow log. Runtime errors (unknown downstream, build failures, etc.)
come from the dispatched downstream-reports workflow on its own — the two
repos stay decoupled.
## Companion changes
* leanprover-community/mathlib-ci#37 : adds the
actions this workflow consumes. This PR bumps the `get-mathlib-ci` SHA pin to ingest this
|
CI |
169/1 |
.github/actions/get-mathlib-ci/action.yml,.github/workflows/pr_check_downstream.yml |
2 |
10 |
['downstream-reports-automation', 'github-actions', 'marcelolynch', 'thorimur'] |
bryangingechen assignee:bryangingechen |
0-10438 2 hours ago |
0-18755 5 hours ago |
0-18524 5 hours |
| 40004 |
jcommelin author:jcommelin |
doc: add wikidata attributes |
This PR adds a batch of wikidata attributes to concepts from overview.yaml.
---
[](https://gitpod.io/from-referrer/)
|
|
45/21 |
Mathlib/Algebra/ContinuedFractions/Basic.lean,Mathlib/Algebra/EuclideanDomain/Defs.lean,Mathlib/Algebra/Group/Action/Defs.lean,Mathlib/Algebra/Group/Defs.lean,Mathlib/Algebra/Group/Hom/Defs.lean,Mathlib/Algebra/Group/Irreducible/Defs.lean,Mathlib/Algebra/Group/Subgroup/Defs.lean,Mathlib/Algebra/Ring/Defs.lean,Mathlib/Algebra/Ring/Hom/Defs.lean,Mathlib/Algebra/Ring/Subring/Defs.lean,Mathlib/CategoryTheory/Abelian/Basic.lean,Mathlib/CategoryTheory/Category/Basic.lean,Mathlib/CategoryTheory/Comma/Basic.lean,Mathlib/CategoryTheory/Functor/Basic.lean,Mathlib/CategoryTheory/Iso.lean,Mathlib/CategoryTheory/Monoidal/Category.lean,Mathlib/CategoryTheory/NatTrans.lean,Mathlib/CategoryTheory/Sites/Grothendieck.lean,Mathlib/Data/Complex/Basic.lean,Mathlib/Data/EReal/Basic.lean,Mathlib/Data/Real/Basic.lean,Mathlib/GroupTheory/FreeGroup/Basic.lean,Mathlib/GroupTheory/GroupAction/Quotient.lean,Mathlib/GroupTheory/Index.lean,Mathlib/GroupTheory/Nilpotent.lean,Mathlib/GroupTheory/Perm/Subgroup.lean,Mathlib/GroupTheory/Schreier.lean,Mathlib/GroupTheory/SpecificGroups/Alternating.lean,Mathlib/GroupTheory/Subgroup/Simple.lean,Mathlib/LinearAlgebra/Span/Defs.lean,Mathlib/NumberTheory/LucasLehmer.lean,Mathlib/RingTheory/FractionalIdeal/Basic.lean,Mathlib/RingTheory/Ideal/Maximal.lean,Mathlib/RingTheory/Ideal/Prime.lean,Mathlib/RingTheory/Ideal/Quotient/Defs.lean,Mathlib/RingTheory/LocalRing/Defs.lean,Mathlib/RingTheory/Noetherian/Defs.lean,Mathlib/RingTheory/UniqueFactorizationDomain/Defs.lean |
38 |
52 |
['SnirBroshi', 'github-actions', 'jcommelin'] |
nobody |
0-4704 1 hour ago |
0-64621 17 hours ago |
0-64390 17 hours |
| 40035 |
marcelolynch author:marcelolynch |
feat(cache): restructure cache tool server-side storage layout |
This PR significantly restructures the cache back-end storage layout to address some security issues and as a side benefit improve auditing, garbage collection, provenance.
1) Instead of setting the cache-universe boundary to the repository, we scope it to particular commit SHAs. This means a review of the changes in a PR does give you confidence in that pulling from the cache at that commit.
2) Split the cache universes from master, forks, and nightly-testing at the infrastructure level, using different azure containers. This has other benefits in management, like better auditing, the possibility of targeted garbage collection, etc.
See `SECURITY.md` for the motivation and explanation of the trust model implemented here.
Also added cache tool tests, and changed a bunch of the messages output to users to surface security concerns more clearly.
Extra details:
### Trust model
- Five containers — `master`, `forks`, `nightly-testing`, `pr-toolchain-tests`,
and `legacy` (the original bare `mathlib4` bucket) — each mapped to a dedicated
Azure container. Every trust level has its own writer identity. Azure RBAC on
the OIDC token is the enforced write boundary, not the workflow logic.
- Reads use a per-repo, trust-ordered chain (most-trusted first, stop at first
hit
- URL layout is fixed per container, not per repo: `master` is flat
(`/f/{hash}`), multi-writer containers namespace by repo (`/f/{repo}/{hash}`),
`legacy` preserves its historical mixed layout for older clients.
### Per-commit scoping & discovery
- Fork uploads are scoped to their commit SHA (`/f/{repo}/{sha}/{hash}`), so a
closed/hidden PR's artifacts can't be served to a later honest PR on the same
fork. A marker blob (`/m/{repo}/{sha}`) is written after a successful upload.
- New `cache query [REF]`: walks history to the merge-base with master and HEAD-
probes markers to report the most recent cached commit (or a boolean probe for
a single ref). `cache get --scope=` then reads that commit's namespace.
- `cache get` prints a security notice whenever a read leaves the repo's
default trust boundary (a scope, a widened `--cache-from`, or a `--repo` that
diverges from the git remote), plus a hint pointing uncached fork HEADs at
`cache query`.
### CLI / env surface
- New flags: `--cache-from=LIST`, `--container=NAME`, `--scope=REF`; new command
`cache query`.
- New env: `MATHLIB_CACHE_FROM`, `MATHLIB_CACHE_REPO_SCOPE`. `MATHLIB_CACHE_GET_URL`
/ `_PUT_URL` retained as single-URL escape hatches; `MATHLIB_CACHE_USE_CLOUDFLARE`
removed.
### CI wiring
- New composite action `cache-trust-dispatch` is the single source mapping
`(repo, branch) → (write container, read chain, per-commit scope)`; `build.yml`,
`bors.yml`, and `build_template.yml` consult it. Trust policy lives in YAML,
not in the Lean tool.
- During migration, master CI dual-writes to `legacy` so older cache clients
keep working; forks/nightly never write to `legacy`.
### Code organization & testing
- Backend split into focused modules: `Cache.Infra` (container model),
`Cache.Cli` (option parsing), `Cache.Marker`, `Cache.Query`, `Cache.Warning`;
`Cache.Init` folded away.
- New standalone `lake exe cache-test` (`Cache.Test`) unit-tests the pure logic —
container model, URL construction, per-repo read chains, flag parsing, and the
warning conditions — without building Mathlib. |
file-removed
CI
|
2372/286 |
.github/actions/cache-trust-dispatch/action.yml,.github/workflows/bors.yml,.github/workflows/build.yml,.github/workflows/build_template.yml,Cache/Cli.lean,Cache/Infra.lean,Cache/Init.lean,Cache/Main.lean,Cache/Marker.lean,Cache/Query.lean,Cache/README.md,Cache/Requests.lean,Cache/SECURITY.md,Cache/Test.lean,Cache/Warning.lean,lakefile.lean |
16 |
1 |
['github-actions'] |
nobody |
0-3235 53 minutes ago |
0-3005 46 minutes ago |
0-4885 1 hour |
| 36888 |
CoolRmal author:CoolRmal |
feat: generalize some lemmas by using conditional Jensen |
This PR includes two possible ways of generalizing `integral_abs_condExp_le`:
1. Replace absolute values with norms.
2. Consider absolute values defined on a lattice with a solid norm.
We also prove that if a function is in Lp then its conditional expectation is also in Lp. In order to prove these results, some of the lemmas about essSup are generalized to conditionally complete lattices.
Created with the help of Codex.
---
- [x] depends on: #36877
- [x] depends on: #39104
[](https://gitpod.io/from-referrer/)
|
t-measure-probability |
260/140 |
Mathlib/MeasureTheory/Function/ConditionalExpectation/Basic.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/CondJensen.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/Real.lean,Mathlib/MeasureTheory/Measure/Trim.lean,Mathlib/Probability/CondVar.lean,Mathlib/Probability/Martingale/BorelCantelli.lean,Mathlib/Probability/Martingale/Centering.lean |
7 |
42 |
['CoolRmal', 'EtienneC30', 'RemyDegenne', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
EtienneC30 assignee:EtienneC30 |
0-3085 51 minutes ago |
0-4430 1 hour ago |
8-21796 8 days |
| 36219 |
gasparattila author:gasparattila |
chore(Order/SupClosed): use `to_dual` |
---
[](https://gitpod.io/from-referrer/)
|
t-order |
66/215 |
Mathlib/Order/ConditionallyCompleteLattice/Finset.lean,Mathlib/Order/SupClosed.lean |
2 |
6 |
['github-actions', 'mathlib-merge-conflicts'] |
nobody |
0-2543 42 minutes ago |
44-30677 44 days ago |
48-34657 48 days |
| 38095 |
astrainfinita author:astrainfinita |
perf(Algebra/*/{InjSurj, TransferInstance}): reduce instance `Expr`s |
---
We can not just use `fast_instance%`, because `fast_instance%` reduces instances into constructor applications, but their arguments may still not be reduced.
This PR continues the work from #13795.
Original PR: https://github.com/leanprover-community/mathlib4/pull/13795
[Zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/instance.20unfolding.20phenomenon/) |
t-algebra label:t-algebra$ |
401/219 |
Mathlib/Algebra/Field/Basic.lean,Mathlib/Algebra/Field/TransferInstance.lean,Mathlib/Algebra/Group/Action/Defs.lean,Mathlib/Algebra/Group/Action/TransferInstance.lean,Mathlib/Algebra/Group/InjSurj.lean,Mathlib/Algebra/Group/TransferInstance.lean,Mathlib/Algebra/GroupWithZero/Action/Defs.lean,Mathlib/Algebra/GroupWithZero/Action/End.lean,Mathlib/Algebra/GroupWithZero/Action/TransferInstance.lean,Mathlib/Algebra/GroupWithZero/InjSurj.lean,Mathlib/Algebra/Module/Defs.lean,Mathlib/Algebra/Module/RingHom.lean,Mathlib/Algebra/Ring/InjSurj.lean,Mathlib/Algebra/Ring/TransferInstance.lean,Mathlib/Util/TermReduce.lean,scripts/noshake.json |
16 |
7 |
['astrainfinita', 'github-actions', 'leanprover-radar'] |
nobody |
0-2542 42 minutes ago |
43-78291 43 days ago |
43-80590 43 days |
| 38821 |
Jun2M author:Jun2M |
feat(Data/List): rotation of sublist is sublist of rotation |
This PR proves `(∃ L₁ : List α, L ~r L₁ ∧ L₁ <+ L') ↔ (∃ L₂ : List α, L <+ L₂ ∧ L₂ ~r L')`.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
10/0 |
Mathlib/Data/List/Rotate.lean |
1 |
3 |
['SnirBroshi', 'eric-wieser', 'github-actions'] |
nobody |
0-2541 42 minutes ago |
28-20859 28 days ago |
28-20628 28 days |
| 38223 |
Deicyde author:Deicyde |
feat(Geometry/Manifold): add `MfldCat`, the category of `C^n` manifolds |
We define `MfldCat 𝕜 n`: the category of `C^n` manifolds over a field `𝕜`, following the pattern of `TopCat` in
`Mathlib.Topology.Category.TopCat.Basic`. We also implement `HasForget₂ (MfldCat 𝕜 n) TopCat`—the forgetful functor into the category of topological spaces. For more discussion see the Zulip thread: [#PR reviews > #38223 The Category of C^n Manifolds](https://leanprover.zulipchat.com/#narrow/channel/144837-PR-reviews/topic/.2338223.20The.20Category.20of.20C.5En.20Manifolds/with/587038032)
Also added: `ContMDiffMap.id_apply`, `.coe_id` and `.coe_comp` which are comparable to `ContinuousMap` API.
### Future work
- ✅ Define a Monoidal structure via product manifolds, analogous to `Manifold.Topology.Category.TopCat.Monoidal` #38560
- ✅ Define the tangent functor: `M ↦ TM`, `F ↦ F.tangentMap` from `MfldCat (n+1) 𝕜` to `MfldCat n 𝕜` #38270
- Functor `FGModuleCat 𝕜 ⥤ MfldCat 𝕜 n` sending a finite-dimensional `𝕜`-vector space to the manifold modeled on itself. Left as `TODO`.
- Define `FGModuleCat 𝕜` as an enriched category over `MfldCat n 𝕜`. Then _smooth functors_ can be realized as endofunctors on the enriched category. This is the main motivation for this construction.
---
[](https://gitpod.io/from-referrer/)
|
t-differential-geometry
new-contributor
t-category-theory
|
224/0 |
Mathlib.lean,Mathlib/Geometry/Manifold/Category/MfldCat/Basic.lean,Mathlib/Geometry/Manifold/ContMDiffMap.lean |
3 |
57 |
['Deicyde', 'chrisflav', 'dagurtomas', 'github-actions', 'idontgetoutmuch', 'peabrainiac'] |
nobody |
0-2540 42 minutes ago |
21-20720 21 days ago |
34-70605 34 days |
| 34759 |
Hagb author:Hagb |
feat(RingTheory/MvPolynomial/MonomialOrder): add degree with `⊥` as degree of `0` |
`withBotDegree` is to distinguish the degree of zero polynomial from the degree of non-zero constant polynomial. `MonomialOrder.degree` of both are 0, while `withBotDegree` is `⊥` for zero polynomial and 0 for non-zero constant polynomial.
`MonomialOrder.withBotDegree` is to `MonomialOrder.degree` as `Polynomial.degree` is to `Polynomial.natDegree`.
It's upstreamized from https://github.com/WuProver/groebner_proj.
---
`MonomialOrder.withBotDegree` is to [`MonomialOrder.degree`](https://leanprover-community.github.io/mathlib4_docs/find/?pattern=MonomialOrder.degree#doc) as [`Polynomial.degree`](https://leanprover-community.github.io/mathlib4_docs/find/?pattern=Polynomial.degree#doc) is to [`Polynomial.natDegree`](https://leanprover-community.github.io/mathlib4_docs/find/?pattern=Polynomial.natDegree#doc).
It's upstreamized from [`Groebner/MonomialOrder.lean` in the repo `WuProver/groebner_proj`](https://github.com/WuProver/groebner_proj/blob/main/Groebner/MonomialOrder.lean).
- [x] ~depends on: #34755~
- [x] depends on: #34756
- [x] depends on: #34758
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
243/2 |
Mathlib/Data/Finsupp/MonomialOrder.lean,Mathlib/RingTheory/MvPolynomial/MonomialOrder.lean |
2 |
17 |
['Hagb', 'github-actions', 'joneugster', 'mariainesdff', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
nobody |
0-2539 42 minutes ago |
21-41946 21 days ago |
56-29786 56 days |
| 34271 |
gasparattila author:gasparattila |
feat(Topology/Sets): second-countability of `(Nonempty)Compacts` |
---
- [x] depends on: #34266
- [x] depends on: #34268
[](https://gitpod.io/from-referrer/)
|
t-topology |
17/76 |
Mathlib/Topology/MetricSpace/Closeds.lean,Mathlib/Topology/Sets/VietorisTopology.lean |
2 |
9 |
['github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot', 'scholzhannah'] |
nobody |
0-2537 42 minutes ago |
21-18709 21 days ago |
58-27381 58 days |
| 36743 |
Jun2M author:Jun2M |
feat(Combinatorics/GraphLike): introduce `GraphLike` typeclass |
Per discussion at ([#graph theory > HasAdj](https://leanprover.zulipchat.com/#narrow/channel/252551-graph-theory/topic/HasAdj/with/575843445)), This PR introduces the `GraphLike` typeclass to capture the notions like `dart` and `walk` across various graph objects, such as `SimpleGraph`, `Graph`, and `Digraph`.
The goal is that by abstracting these core components into a typeclass, we can prove these results once for all graph-like structures rather than duplicating them across different graph types.
### Main definitions
* `GraphLike V D E Gr`: A typeclass parameterized by a vertex type `V`, dart type `D` and a graph type `Gr` (with `V`, `D` & `E` as an `outParam`).
* `GraphLike.verts : Set V`: The set of vertices of the graph.
* `GraphLike.darts : Set D`: The set of darts of the graph.
* `GraphLike.edges : Set E`: The set of edges of the graph.
* `GraphLike.Adj : V → V → Prop`: The adjacency relation, defined by default as `∃ d ∈ darts, fst d = u ∧ snd d = v`.
---
This PR generalises #35776 to also unify `Graph`.
PRs depending on this PR are
#39047 (graphLike with no multi edges) => #39050 (Digraph is graphLike)
||
V
#36829 (undirected graphLike) => #39053 (Graph is graphLike) & #39054 (Simplegraph is graphLike)
||
V
#36756 (def of walk on GraphLike) => #36971 (change Simplegraph to use GraphLike walk)
[](https://gitpod.io/from-referrer/)
|
t-combinatorics |
104/0 |
Mathlib.lean,Mathlib/Combinatorics/GraphLike/Basic.lean |
2 |
78 |
['IvanRenison', 'Jun2M', 'SnirBroshi', 'YaelDillies', 'github-actions', 'lauramonk', 'mathlib-merge-conflicts'] |
nobody |
0-2536 42 minutes ago |
21-33346 21 days ago |
72-31531 72 days |
| 38785 |
scholzhannah author:scholzhannah |
feat: use `alias_in` attribute for CW complexes |
Using the `alias_in` attribute for classical CW complexes to get rid of the `export` sections.
---
[](https://gitpod.io/from-referrer/)
|
t-topology |
103/58 |
Mathlib/Topology/CWComplex/Classical/Basic.lean,Mathlib/Topology/CWComplex/Classical/Finite.lean,Mathlib/Topology/CWComplex/Classical/Subcomplex.lean |
3 |
8 |
['github-actions', 'grunweg', 'scholzhannah'] |
nobody |
0-2536 42 minutes ago |
21-63210 21 days ago |
28-51341 28 days |
| 39868 |
JuanCoRo author:JuanCoRo |
feat(Algebra/Polynomial): linearity of `divByMonic` and adjacent results |
---
This PR adds the `R`-linearity of the monic polynomial division map `_ /ₘ q`. It also adds adjacent results that stem from this work.
#### Refactors:
- Reuses the proofs from `add_modByMonic` and `smul_modByMonic` to generalize these results to `add_div_modByMonic` and `smul_div_modByMonic` respectively.
- Replaces the proofs of `add_modByMonic` and `smul_modByMonic` as specializations of the more general theorems `add_div_modByMonic` and `smul_div_modByMonic` respectively.
#### Additions:
- Adds the necessary results for `_ /ₘ q` linearity:
- `add_divByMonic : (p₁ + p₂) /ₘ q = p₁ /ₘ q + p₂ /ₘ q`
- `smul_divByMonic : c • p /ₘ q = c • (p /ₘ q)`
- Adds `_ /ₘ q` as an `R`-linear map:
- `divByMonicHom`: definition of `_ /ₘ q` as a linear map
- `mem_ker_divByMonic`: kernel characterization for `_ /ₘ q`.
- In `Div.lean` adds dual results for `/ₘ` that were already present for `%ₘ`
- `neg_divByMonic : (-p) /ₘ q = -(p /ₘ q)`
- `sub_divByMonic : (p₁ - p₂) /ₘ q = p₁ /ₘ q - p₂ /ₘ q`
- `mul_divByMonic_assoc (hd : q ∣ p₂) : (p₁ * p₂) /ₘ q = p₁ * (p₂ /ₘ q)`
While `mul_divByMonic_assoc` is not exactly the dual of `mul_modByMonic`, I thought it wouldn't hurt to add it.
[](https://gitpod.io/from-referrer/) |
new-contributor
t-algebra
label:t-algebra$ |
54/17 |
Mathlib/Algebra/Polynomial/Div.lean,Mathlib/Algebra/Polynomial/RingDivision.lean |
2 |
4 |
['github-actions', 'wwylele'] |
nobody |
0-2159 35 minutes ago |
0-52203 14 hours ago |
0-52051 14 hours |
| 39755 |
wwylele author:wwylele |
chore(GroupTheory): remove a defeq abuse |
---
I am not sure if this is the right change to make, so I'd like to start a discussion from this. The issue here seems to be that the simp lemma [MulAction.orbitRel.Quotient.orbit_mk](https://leanprover-community.github.io/mathlib4_docs/Mathlib/GroupTheory/GroupAction/Defs.html#MulAction.orbitRel.Quotient.orbit_mk) fired and changed the underlying type of variables in the expression, which is not defeq at instance transparency, and fails defeq check for `MulAction` ([MulAction.instElemOrbit](https://leanprover-community.github.io/mathlib4_docs/Mathlib/GroupTheory/GroupAction/Defs.html#MulAction.instElemOrbit) vs [MulAction.instElemOrbit_1](https://leanprover-community.github.io/mathlib4_docs/Mathlib/GroupTheory/GroupAction/Defs.html#MulAction.instElemOrbit_1)). The easy change here is to disable the offending simp, but it feels like a common language pitfall. Should we do either of the following instead?
- remove `MulAction.orbitRel.Quotient.orbit_mk` from default simp set
- Make the the orbit definition more transparent
[](https://gitpod.io/from-referrer/)
|
tech debt
t-group-theory
|
1/2 |
Mathlib/GroupTheory/GroupAction/Basic.lean |
1 |
1 |
['github-actions'] |
nobody |
0-1988 33 minutes ago |
6-24646 6 days ago |
6-24415 6 days |
| 38957 |
wwylele author:wwylele |
chore(GroupTheory/DivisibleHull): remove `backward.privateInPublic` |
---
[](https://gitpod.io/from-referrer/)
|
tech debt
t-group-theory
|
5/12 |
Mathlib/GroupTheory/DivisibleHull.lean |
1 |
13 |
['Komyyy', 'github-actions', 'grunweg', 'jcommelin', 'wwylele'] |
jcommelin assignee:jcommelin |
0-1976 32 minutes ago |
4-1385 4 days ago |
17-79504 17 days |
| 37712 |
eric-wieser author:eric-wieser |
feat: add a `LawfulXor` typeclass |
I've put this in mathlib since it can use `Function.Involutive`; it can of course be upstreamed at a later date.
Having this generalization encourages downstream code in cslib to be expressed in terms of involutive functions, rather than just `^^^` on bitvectors.
---
[](https://gitpod.io/from-referrer/)
|
t-data |
130/0 |
Mathlib.lean,Mathlib/Data/LawfulXor.lean |
2 |
6 |
['eric-wieser', 'github-actions', 'linesthatinterlace'] |
TwoFX assignee:TwoFX |
0-1203 20 minutes ago |
24-2173 24 days ago |
30-80934 30 days |
| 38375 |
WenrongZou author:WenrongZou |
feat(MvPowerSeries): some lemmas `truncTotal` of `subst` |
This PR adds some lemmas about truncation of total degree of a substitution.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory |
154/7 |
Mathlib/RingTheory/MvPowerSeries/Substitution.lean,Mathlib/RingTheory/MvPowerSeries/Trunc.lean |
2 |
3 |
['BryceT233', 'github-actions'] |
riccardobrasca assignee:riccardobrasca |
0-1202 20 minutes ago |
17-52227 17 days ago |
37-36110 37 days |
| 38527 |
archiebrowne author:archiebrowne |
feat(Analysis/Calculus): continuously differentiable actions |
define the class `ContDiffSMul 𝕜 M X n` which asserts that the map `(c, x) ↦ c • x` is `n` times continuously differentiable on `M × X`.
Many of the results are the C^n analogues of those in the module Mathlib.Topology.Algebra.MulAction.
|
t-differential-geometry
new-contributor
|
317/24 |
Mathlib.lean,Mathlib/Analysis/Calculus/BumpFunction/Basic.lean,Mathlib/Analysis/Calculus/ContDiff/Operations.lean,Mathlib/Analysis/Calculus/IteratedDeriv/Lemmas.lean,Mathlib/Analysis/ContDiffMulAction.lean,Mathlib/Analysis/InnerProductSpace/Calculus.lean |
6 |
11 |
['archiebrowne', 'github-actions', 'grunweg', 'peabrainiac'] |
ocfnash assignee:ocfnash |
0-1201 20 minutes ago |
22-18401 22 days ago |
30-4079 30 days |
| 38551 |
TTony2019 author:TTony2019 |
feat(Analysis/Convex/Intrinsic): add `affineSpan_prod_eq` and `intrinsicInterior_prod_eq` |
### Summary
We prove that the affine span of a product set equals the product of the affine spans, and that the intrinsic interior of a product set equals the product of the intrinsic interiors.
- `affineSpan_prod_eq`: for `s : Set P₁` and `t : Set P₂`, `affineSpan k (s ×ˢ t) = (affineSpan k s) ×ˢ (affineSpan k t)` as sets.
- `intrinsicInterior_prod_eq`: for `s : Set P` and `t : Set Q`, `intrinsicInterior 𝕜 (s ×ˢ t) = intrinsicInterior 𝕜 s ×ˢ intrinsicInterior 𝕜 t`.
These two theorems are added to `Mathlib/LinearAlgebra/AffineSpace/AffineSubspace/Basic.lean` and `Mathlib/Analysis/Convex/Intrinsic.lean`.
### Collaboration
Co-authored-by: @imathwy |
new-contributor
t-analysis
|
144/0 |
Mathlib/Algebra/AddTorsor/Basic.lean,Mathlib/Algebra/Group/Pointwise/Set/Basic.lean,Mathlib/Analysis/Convex/Intrinsic.lean,Mathlib/LinearAlgebra/AffineSpace/AffineSubspace/Basic.lean,Mathlib/LinearAlgebra/Prod.lean |
5 |
24 |
['TTony2019', 'github-actions', 'wwylele'] |
themathqueen assignee:themathqueen |
0-1200 20 minutes ago |
30-83302 30 days ago |
33-26944 33 days |
| 38873 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Constructions/BorelSpace/Real` |
- rewrites `measurable_const_mul` by splitting off the `c = 0` case and proving the nonzero case via `measurable_of_continuousOn_compl_singleton`
- replaces the ad hoc case analysis on `⊥`, `⊤`, and real coefficients with a direct continuity argument for multiplication on `EReal`
Extracted from #38104
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
t-measure-probability
|
5/19 |
Mathlib/MeasureTheory/Constructions/BorelSpace/Real.lean |
1 |
3 |
['LorenzoLuccioli', 'github-actions', 'yuanyi-350'] |
RemyDegenne assignee:RemyDegenne |
0-1199 19 minutes ago |
23-5059 23 days ago |
26-15937 26 days |
| 38885 |
yuanyi-350 author:yuanyi-350 |
refactor(MeasureTheory): golf `Mathlib/MeasureTheory/Function/LpOrder` |
- rewrites `coeFn_nonneg` to use the `Lp.coeFn_zero` eventual equality directly via `trans_le`, instead of a separate `filter_upwards` proof
Extracted from #38104
[](https://gitpod.io/from-referrer/) |
codex
LLM-generated
t-measure-probability
|
1/4 |
Mathlib/MeasureTheory/Function/LpOrder.lean |
1 |
2 |
['github-actions', 'yuanyi-350'] |
sgouezel assignee:sgouezel |
0-1198 19 minutes ago |
26-41886 26 days ago |
26-41655 26 days |
| 38895 |
emlis42 author:emlis42 |
chore(Algebra/ContinuedFractions): golf |
This PR simplifies some proofs in `Algebra/ContinuedFractions` |
t-algebra
new-contributor
label:t-algebra$ |
39/63 |
Mathlib/Algebra/ContinuedFractions/Computation/ApproximationCorollaries.lean,Mathlib/Algebra/ContinuedFractions/Computation/Approximations.lean,Mathlib/Algebra/ContinuedFractions/Computation/CorrectnessTerminating.lean,Mathlib/Algebra/ContinuedFractions/Computation/TerminatesIffRat.lean,Mathlib/Algebra/ContinuedFractions/Computation/Translations.lean,Mathlib/Algebra/ContinuedFractions/ContinuantsRecurrence.lean,Mathlib/Algebra/ContinuedFractions/ConvergentsEquiv.lean |
7 |
2 |
['github-actions'] |
joelriou assignee:joelriou |
0-1197 19 minutes ago |
25-5560 25 days ago |
25-80032 25 days |
| 38983 |
kebekus author:kebekus |
feat: Invariance of `meromorphic in normal form` under composition. |
Establish invariance of `meromorphic in normal form` under composition with analytic functions of non-vanishing derivative.
---
[](https://gitpod.io/from-referrer/)
|
t-analysis
maintainer-merge
|
42/0 |
Mathlib/Analysis/Meromorphic/NormalForm.lean |
1 |
12 |
['github-actions', 'kebekus', 'themathqueen'] |
ADedecker assignee:ADedecker |
0-1196 19 minutes ago |
15-37075 15 days ago |
22-57843 22 days |
| 39655 |
joelriou author:joelriou |
feat(CategoryTheory): the κ-accessible category of κ-directed posets |
Given a regular cardinal `κ : Cardinal.{u}`, we show that the category `CardinalFilteredPoset κ` of `κ`-directed partially ordered types (with order embeddings as morphisms) is a `κ`-accessible category.
---
- [x] depends on: #39669
[](https://gitpod.io/from-referrer/)
|
t-category-theory |
188/2 |
Mathlib/CategoryTheory/Presentable/CardinalDirectedPoset.lean |
1 |
2 |
['github-actions', 'mathlib-dependent-issues'] |
robin-carlier assignee:robin-carlier |
0-1194 19 minutes ago |
0-44060 12 hours ago |
0-56770 15 hours |
| 39729 |
grunweg author:grunweg |
chore(Geometry/Manifold): make some doc-strings follow the style guide |
such as, by them beginning with the object they are defining as a subject.
This will yield much better doc-strings for the differential geometry elaborators in #39677.
It also increases conformance with the [documentation style guide](https://github.com/leanprover/lean4/blob/master/doc/style.md).
Inspired by the MI retreat in Lisbon.
---
[](https://gitpod.io/from-referrer/)
|
t-differential-geometry |
30/20 |
Mathlib/Geometry/Manifold/ContMDiff/Defs.lean,Mathlib/Geometry/Manifold/MFDeriv/Defs.lean,Mathlib/Geometry/Manifold/MFDeriv/NormedSpace.lean |
3 |
2 |
['github-actions', 'grunweg'] |
PatrickMassot assignee:PatrickMassot |
0-1193 19 minutes ago |
7-6665 7 days ago |
7-6434 7 days |
| 39753 |
mathlib-splicebot author:mathlib-splicebot |
feat: the sigma-algebra generated by the constant indicator of a set is smaller than the one generated by the set |
This PR was automatically created from PR #37259 by @EtienneC30 via a [review comment](https://github.com/leanprover-community/mathlib4/pull/37259#discussion_r3292960152) by @EtienneC30. |
t-measure-probability |
6/0 |
Mathlib/MeasureTheory/MeasurableSpace/MeasurablyGenerated.lean |
1 |
2 |
['EtienneC30', 'github-actions'] |
EtienneC30 assignee:EtienneC30 |
0-1192 19 minutes ago |
6-38714 6 days ago |
6-38934 6 days |
| 39770 |
mathlib-splicebot author:mathlib-splicebot |
feat: atoms of a countably generated measurable space |
This PR adds a definition for the atoms in a countably generated measurable space, expressed with `natGeneratingSequence`.
We also show that the atoms are measurable sets.
---
This PR was automatically created from PR #39739 by @RemyDegenne via a [review comment](https://github.com/leanprover-community/mathlib4/pull/39739#discussion_r3294476245) by @RemyDegenne. |
t-measure-probability |
121/0 |
Mathlib/MeasureTheory/MeasurableSpace/CountablyGenerated.lean |
1 |
4 |
['RemyDegenne', 'gaetanserre', 'github-actions'] |
EtienneC30 assignee:EtienneC30 |
0-1190 19 minutes ago |
5-47718 5 days ago |
5-47487 5 days |
| 39819 |
mathlib-splicebot author:mathlib-splicebot |
feat: variants of lemmas in CondJensen with a.e. inequalities for the trimmed measure |
This PR was automatically created from PR #35349 by @RemyDegenne via a [review comment](https://github.com/leanprover-community/mathlib4/pull/35349#discussion_r3298163528) by @RemyDegenne. |
t-measure-probability |
34/0 |
Mathlib/MeasureTheory/Function/ConditionalExpectation/CondJensen.lean |
1 |
1 |
['github-actions'] |
EtienneC30 assignee:EtienneC30 |
0-1189 19 minutes ago |
4-47186 4 days ago |
4-46955 4 days |
| 39990 |
grunweg author:grunweg |
chore: move Data/Nat/Lattice to Order |
This file uses only order theory: that is a much better location
---
[](https://gitpod.io/from-referrer/)
|
tech debt
file-removed
|
19/19 |
Mathlib.lean,Mathlib/Algebra/Polynomial/Div.lean,Mathlib/Combinatorics/SimpleGraph/Clique.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/VertexColoring.lean,Mathlib/Data/ENat/Lattice.lean,Mathlib/Data/List/PeriodicityLemma.lean,Mathlib/Data/Multiset/Interval.lean,Mathlib/Data/NNReal/Basic.lean,Mathlib/Data/Set/Accumulate.lean,Mathlib/Dynamics/PeriodicPts/Lemmas.lean,Mathlib/Dynamics/TopologicalEntropy/DynamicalEntourage.lean,Mathlib/MeasureTheory/SetSemiring.lean,Mathlib/Order/Interval/Set/OrdConnectedLinear.lean,Mathlib/Order/Lattice/Nat.lean,Mathlib/Order/OrderIsoNat.lean,Mathlib/RingTheory/Nilpotent/Basic.lean,Mathlib/RingTheory/Nilpotent/Defs.lean,Mathlib/Topology/Instances/Nat.lean,Mathlib/Topology/Metrizable/Uniformity.lean |
19 |
6 |
['SnirBroshi', 'github-actions', 'grunweg'] |
JovanGerb assignee:JovanGerb |
0-1188 19 minutes ago |
1-19106 1 day ago |
1-18877 1 day |
| 40014 |
vasnesterov author:vasnesterov |
feat(Tactic/ComputeAsymptotics/Multiseries): basic constructions |
Introduce basic constructions for multiseries: `const`, `monomial`, `monomialRpow`.
---
[](https://gitpod.io/from-referrer/)
|
t-meta |
356/9 |
Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/ComputeAsymptotics/Multiseries/Basic.lean,Mathlib/Tactic/ComputeAsymptotics/Multiseries/Basis.lean,Mathlib/Tactic/ComputeAsymptotics/Multiseries/Defs.lean |
5 |
1 |
['github-actions'] |
thorimur assignee:thorimur |
0-1187 19 minutes ago |
0-40971 11 hours ago |
0-40892 11 hours |
| 40017 |
vasnesterov author:vasnesterov |
feat(Tactic/ComputeAsymptotics/Multiseries): define `Trimmed` |
Define `Trimmed` predicate and prove basic lemmas about it.
---
[](https://gitpod.io/from-referrer/)
|
t-meta |
170/5 |
Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/ComputeAsymptotics/Multiseries/Basis.lean,Mathlib/Tactic/ComputeAsymptotics/Multiseries/Defs.lean,Mathlib/Tactic/ComputeAsymptotics/Multiseries/Trimming.lean |
5 |
1 |
['github-actions'] |
dwrensha assignee:dwrensha |
0-1186 19 minutes ago |
0-38098 10 hours ago |
0-37867 10 hours |
| 40026 |
thefundamentaltheor3m author:thefundamentaltheor3m |
feat(ArithmeticFunction/Defs): A power of a multiplicative arithmetic function is multiplicative |
---
[](https://gitpod.io/from-referrer/)
|
t-number-theory
new-contributor
|
9/0 |
Mathlib/NumberTheory/ArithmeticFunction/Defs.lean |
1 |
2 |
['github-actions', 'wwylele'] |
MichaelStollBayreuth assignee:MichaelStollBayreuth |
0-1185 19 minutes ago |
0-27648 7 hours ago |
0-27417 7 hours |
| 40031 |
EtienneC30 author:EtienneC30 |
chore: fix deprecations for PMF.bernoulli |
Some statements about `PMF.bernoulli` were not deprecated while `PMF.bernoulli` was deprecated, see https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Deprecation.20policy/near/598588742.
The two lemmas about the support of `PMF.bernoulli` are deprecated in favor of [ProbabilityTheory.bernoulliMeasure_apply_of_notMem_of_notMem](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Probability/Distributions/Bernoulli.html#ProbabilityTheory.bernoulliMeasure_apply_of_notMem_of_notMem).
[PMF.binomial_one_eq_bernoulli](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Probability/ProbabilityMassFunction/Binomial.html#PMF.binomial_one_eq_bernoulli) should wait for #37736 which deprecates `PMF.binomial`.
---
[](https://gitpod.io/from-referrer/)
|
t-measure-probability |
4/4 |
Mathlib/Probability/ProbabilityMassFunction/Constructions.lean |
1 |
1 |
['github-actions'] |
RemyDegenne assignee:RemyDegenne |
0-1184 19 minutes ago |
0-11420 3 hours ago |
0-11189 3 hours |
| 39771 |
kim-em author:kim-em |
feat(GroupTheory/PCore): define the `p`-core of a subgroup |
This PR adds `Subgroup.pCore p H`, the largest normal `p`-subgroup of a subgroup `H : Subgroup G` (classically `O_p(H)`), defined as the supremum of all normal `p`-subgroups. Even without finiteness or primality hypotheses, this is itself a normal `p`-group (the family of normal `p`-subgroups is directed under `≤`, so every element of the supremum lies in some specific summand). For the classical `O_p(G)`, take `pCore p (⊤ : Subgroup G)`.
API covers the universal-property characterisations (`le_pCore`, `normal_le_pCore`, `mem_pCore_iff`, `pCore_eq_bot_iff`, `pCore_eq_top_iff`, `pCore_zero`, `pCore_one`), the Sylow alignment `pCore p H = ⨅ P : Sylow p H, (P : Subgroup H)`, and behaviour under group homomorphisms via `MonoidHom.subgroupMap` and `MonoidHom.subgroupComap` (`map_pCore_le_pCore`, `comap_pCore_eq_pCore` and friends, `MulEquiv.map_pCore`).
Also adds `Subgroup.normal_iSup_normal` in `Mathlib/Algebra/Group/Subgroup/Pointwise.lean` (the supremum of a family of normal subgroups is normal) as the sibling of the existing `normal_iInf_normal`, and `ker_subgroupComap` in `Mathlib/Algebra/Group/Subgroup/Ker.lean` alongside the existing `ker_subgroupMap`. Both marked `@[to_additive]`.
Used downstream in [leanprover/lean-eval#311](https://github.com/leanprover/lean-eval/pull/311) to state the Baer-Suzuki theorem as a [lean-eval](https://lean-lang.org/eval) problem.
🤖 Prepared with Claude Code |
t-group-theory |
272/0 |
Mathlib.lean,Mathlib/Algebra/Group/Subgroup/Ker.lean,Mathlib/Algebra/Group/Subgroup/Pointwise.lean,Mathlib/GroupTheory/PCore.lean |
4 |
13 |
['SnirBroshi', 'Whysoserioushah', 'adomani', 'github-actions', 'kim-em', 'tb65536'] |
tb65536 assignee:tb65536 |
0-1162 19 minutes ago |
4-52290 4 days ago |
4-54826 4 days |
| 38534 |
AlexeyMilovanov author:AlexeyMilovanov |
refactor(Computability): bundle PFun into a structure with FunLike instance |
This PR refactors `PFun` from `def PFun α β := α → Part β` to a structure with a `FunLike` instance.
[Discussion](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Fix.20for.20fun_prop.20on.20PFun.20.28context.3A.20Computability.20Theory.29)
### Main changes
* `PFun` is now a structure with a single field `toFun : α → Part β`.
* Added the `FunLike (α →. β) α (Part β)` instance and `initialize_simps_projections`.
* Added the basic projection/application simp lemmas needed for the structure wrapper.
* Definitions which used to return raw lambdas as partial functions now explicitly use `PFun.mk` or `PFun.lift`.
* Equality proofs for partial functions now use `PFun.ext` / `DFunLike.ext` where `funext` no longer applies directly.
### Downstream impact
The refactor mainly impacts Computability Theory and Category Theory (`Category/PartialFun.lean`). Since `PFun` is no longer definitionally equal to `α → Part β`, tactics such as `rfl`, `simp`, and `funext` can no longer always see through the old raw-function representation.
As a result, several proofs (e.g. `fix_aux`, `ppred`, `mem_eval`, and `unitIso`) grew in size, requiring explicit `ext` + `simp` breakdowns. I tried to keep these proof changes minimal; further golfing suggestions are very welcome. It seems that fully recovering the old brevity in some places may require additional `PFun`-specific API/congruence support, which I avoided adding in this PR to keep the diff minimal.
### Affected files
* **Core:** `Mathlib/Data/PFun.lean`
* **Computability:** `Partrec`, `PartrecBasis`, `PartrecCode`, `RE`, `RecursiveIn`, `Ackermann`, `Halting`, `StateTransition`, `TuringDegree`, `TuringMachine/Config`
* **Category Theory:** `Category/PartialFun.lean`
* **Other:** `Data/Finset/PImage.lean`, `NumberTheory/Dioph.lean`
This also removes the previous `set_option linter.flexible false` workaround and the local transparency workaround in `TuringMachine/Config.lean`, as well as the local transparency workarounds in `Category/PartialFun.lean`.
### Note on LLM usage
The core `PFun` change caused numerous downstream errors. I initially used an LLM to help draft fixes for these files. Afterwards, I spent a significant amount of time manually correcting and modifying all of the generated changes.
|
new-contributor
t-computability
|
821/599 |
Mathlib/CategoryTheory/Category/PartialFun.lean,Mathlib/Computability/Ackermann.lean,Mathlib/Computability/Halting.lean,Mathlib/Computability/Partrec.lean,Mathlib/Computability/PartrecBasis.lean,Mathlib/Computability/PartrecCode.lean,Mathlib/Computability/RE.lean,Mathlib/Computability/RecursiveIn.lean,Mathlib/Computability/StateTransition.lean,Mathlib/Computability/TuringDegree.lean,Mathlib/Computability/TuringMachine/Config.lean,Mathlib/Data/Finset/PImage.lean,Mathlib/Data/PFun.lean,Mathlib/NumberTheory/Dioph.lean |
14 |
9 |
['AlexeyMilovanov', 'dagurtomas', 'github-actions', 'j-loreaux', 'mathlib-bors', 'mathlib-merge-conflicts'] |
nobody |
0-581 9 minutes ago |
4-15207 4 days ago |
12-42719 12 days |
| Number |
Author |
Title |
Description |
Labels |
+/- |
Modified files (first 100) |
📝 |
💬 |
All users who commented or reviewed |
Assignee(s) |
Updated |
Last status change |
total time in review |
| 38344 |
robo7179 author:robo7179 |
feat(SimpleGraph/Coloring/VertexColoring): Matching is 2 colorable |
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
51/0 |
Mathlib/Combinatorics/SimpleGraph/Coloring/VertexColoring.lean |
1 |
5 |
['SnirBroshi', 'github-actions', 'vlad902'] |
nobody |
34-52578 1 month ago |
38-20122 38 days ago |
38-20277 38 days |
| 38364 |
openendings author:openendings |
feat: create Order/DirectedCompletePartialOrder/Defs.lean |
Define DirectedCompletePartialOrder and its interaction with iSup and sSup.
---
A DirectedCompletePartialOrder is equivalently:
- a partial order with LUBs of nonempty directed sets;
- what happens when you remove ⊥ from a CompletePartialOrder; or
- a ConditionallyCompletePartialOrder in which every directed set is BddAbove.
Like CPOs, DCPOs are commonly studied in denotational semantics.
Potential applications:
- [#Is there code for X? > Summing `ENat`s without topology](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Summing.20.60ENat.60s.20without.20topology/with/590070848) -- defining infinite sums in an DCPO-enriched `AddCommMonoidWithTop` such as `ENat` or `ENNReal`.
- [#Is there code for X? > Scott Induction](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Scott.20Induction/with/590112858) -- fixpoint theorems similar to `OmegaCompletePartialOrder`, generalised to arbitrary cardinalities.
[](https://gitpod.io/from-referrer/)
|
t-order
new-contributor
|
123/0 |
Mathlib.lean,Mathlib/Order/DirectedCompletePartialOrder/Defs.lean,docs/references.bib |
3 |
4 |
['SnirBroshi', 'github-actions', 'openendings'] |
nobody |
31-10434 1 month ago |
37-554 37 days ago |
37-61549 37 days |
| 38316 |
tannerduve author:tannerduve |
feat(Order/OmegaCompletePartialOrder): least fixed point and Scott induction |
Adds `ContinuousHom.lfp` for endomorphisms on an ωCPO with `⊥`, as the `ωSup` of the iterate chain from `⊥`, together with `map_lfp`, `isFixedPt_lfp`, `lfp_le_fixed`, `isLeast_lfp`, and the Scott induction theorem `lfp_induction` (specialized from a more general seed-based `ωSup_iterate_induction`).
For `Part.fix`, adds:
* `Part.exists_mem_approx_of_mem_fix`: if `y ∈ Part.fix g x`, some finite approximation of `g` already contains `y`.
* `Part.Fix.approx_eq_iterate_bot` and `Part.Fix.approxChain_eq_iterateChain`: bridges between `Fix.approx`/`approxChain` and `f^[n] ⊥`/`iterateChain`.
* `Part.fix_eq_lfp`: `Part.fix g = ContinuousHom.lfp (.ofFun g hc)` when `g` is ω-Scott continuous.
* `Part.fix_scott_induction`: Scott induction specialized to `Part.fix`.
* `Part.fix_induction_mem`: membership induction on `Part.fix`, derived from `fix_scott_induction`. |
new-contributor |
114/0 |
Mathlib/Control/LawfulFix.lean,Mathlib/Order/OmegaCompletePartialOrder.lean,docs/references.bib |
3 |
2 |
['github-actions'] |
nobody |
27-26914 27 days ago |
39-3016 39 days ago |
39-3311 39 days |
| 38871 |
0xTerencePrime author:0xTerencePrime |
feat(Combinatorics/SimpleGraph): add parity lemmas for outer and inner vertices |
Adds three lemmas to `SimpleGraph.DegreeSum`:
- `sum_degrees_option_zmod_two`: the handshaking lemma for `Option I` over ZMod 2
- `degree_none_zmod_two_eq_sum`: simp-normal form of the above
- `card_degree_one_option_eq_outer_zmod_two`: under degree bound ≤ 2, count of degree-1 inner vertices equals outer vertex degree mod 2 |
t-combinatorics
new-contributor
|
65/3 |
Mathlib/Combinatorics/SimpleGraph/DegreeSum.lean |
1 |
6 |
['0xTerencePrime', 'SnirBroshi', 'github-actions'] |
nobody |
25-76399 25 days ago |
26-46627 26 days ago |
26-46396 26 days |
| 38897 |
0xTerencePrime author:0xTerencePrime |
feat(Combinatorics/SetFamily): formalize 1D Sperner's Lemma parity |
Formalizes the 1-dimensional Sperner's Lemma (parity version): given a coloring of
the `n + 1` vertices of a subdivided line segment with two colors (`ZMod 2`), if the
two endpoints have different colors, then the number of color-changing edges is odd.
This is **distinct** from `IsAntichain.sperner` in `SetFamily.LYM`, which concerns
antichains in a power set. This file formalizes the topological/combinatorial parity
statement used as the base case in higher-dimensional Sperner arguments.
## Key declarations
- `SpernerColoring`: type-safe coloring via `Fin (n + 1) → ZMod 2`
- `edgeDiff`: color difference on adjacent vertices, computed in `ZMod 2`
- `totalDiff`: telescoping sum of all edge differences
- `diffEdges`: the `Finset` of bichromatic (color-changing) edges
- `sperner_1d`: main theorem — `Odd (diffEdges c).card`
## Design notes
- Using `Fin (n + 1) → ZMod 2` instead of `ℕ → ZMod 2` makes boundary conditions
unrepresentable at the type level, eliminating out-of-bounds cases entirely.
- The proof reduces to a telescoping sum in `ZMod 2`, using `CharTwo.add_self_eq_zero`
to cancel all interior vertices, avoiding parity case splits.
This is intended as the 1D base case, the approach generalizes to higher-dimensional
Sperner's Lemma in future work.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
133/0 |
Mathlib.lean,Mathlib/Combinatorics/SetFamily/Sperner1D.lean |
2 |
3 |
['github-actions', 'grunweg'] |
nobody |
25-67633 25 days ago |
25-77783 25 days ago |
25-77552 25 days |
| 38951 |
thomaskwaring author:thomaskwaring |
feat(Order/PrimeSeparator): remove unnecessary hypotheses |
In `mem_ideal_sup_principal`, boundedness and distributivity were unused, and in `prime_ideal_of_disjoint_filter_ideal`, boundedness was only used to produce an element of the filter `F`, which is already nonempty by definition.
---
[](https://gitpod.io/from-referrer/)
|
t-order
new-contributor
|
9/19 |
Mathlib/Order/PrimeSeparator.lean |
1 |
2 |
['github-actions'] |
nobody |
24-60324 24 days ago |
24-60411 24 days ago |
24-60180 24 days |
| 38310 |
ZRTMRH author:ZRTMRH |
feat(Combinatorics/Quiver/Schreier): word evaluation and reachability |
Adds word evaluation and reachability results to the Schreier graph API.
* `SchreierGraph.evalWord` : evaluates a word `List (S × Bool)` as an element of the ambient group, where `(s, true)` contributes `ι s` and `(s, false)` contributes `(ι s)⁻¹`.
* `SchreierGraph.evalWord_eq_lift` : agreement with `FreeGroup.lift`.
* `SchreierGraph.evalWord_mem_closure` : every word evaluates into the subgroup generated by `ι`.
* `SchreierGraph.pathFromWord` : a Bool-tagged word yields a path in `Symmetrify (SchreierGraph V ι)` from `x` to `evalWord ι w • x`.
* `SchreierGraph.reachable_iff` : two vertices are connected by a path in the symmetrification iff some element of the subgroup closure carries one to the other.
Follow-up to #36320.
This PR was written with AI assistance (Claude). The code has been reviewed by the author.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-combinatorics
large-import
LLM-generated
|
157/0 |
Mathlib/Combinatorics/Quiver/Schreier.lean |
1 |
2 |
['github-actions'] |
nobody |
22-74339 22 days ago |
39-21413 39 days ago |
39-21182 39 days |
| 39023 |
TBUGTB author:TBUGTB |
feat(Algebra/Order): API lemmas on floor and abs |
Co-authored-by: Etienne Marion @EtienneC30
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
brownian
new-contributor
label:t-algebra$ |
9/0 |
Mathlib/Algebra/Order/Floor/Semiring.lean,Mathlib/Algebra/Order/Ring/Abs.lean |
2 |
3 |
['TBUGTB', 'github-actions'] |
nobody |
22-56065 22 days ago |
22-59254 22 days ago |
22-59023 22 days |
| 37190 |
cjrl author:cjrl |
feat(Combinatorics): Set-Valued Pigeonhole Principle |
This PR contributes two theorems to combinatorics:
- `exists_lt_card_cover_of_card_biUnion_lt_card` is a set-valued version of the pigeonhole principle.
- `sum_card_eq_sum_card_cover_biUnion` is a set theoretic corollary of a double counting result proved for bipartite graphs (`Finset.sum_card_bipartiteAbove_eq_sum_card_bipartiteBelow`). This was needed to prove the above pigeonhole principle.
The motivation for these results is our Latin Square PR #36698. These results were proved in less general terms in that PR, but are independent of Latin Square considerations and so we have generalized and moved them into more relevant files.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-combinatorics
|
38/0 |
Mathlib/Combinatorics/Enumerative/DoubleCounting.lean,Mathlib/Combinatorics/Pigeonhole.lean |
2 |
16 |
['IvanRenison', 'cjrl', 'ghseeli', 'github-actions', 'j-loreaux', 'vlad902'] |
b-mehta assignee:b-mehta |
21-1691 21 days ago |
47-22187 47 days ago |
62-79155 62 days |
| 38309 |
ntapiam author:ntapiam |
feat(Algebra/NonAssoc): dendriform algebras |
Define dendriform semirings and algebras
---
This PR introduces dendriform structures such as dendriform semirings
and algebras, and proves basic facts linking them to their pre-Lie
counterparts.
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
270/0 |
Mathlib.lean,Mathlib/Algebra/NonAssoc/Dendriform/Defs.lean,docs/references.bib |
3 |
5 |
['dagurtomas', 'github-actions', 'ntapiam'] |
ocfnash assignee:ocfnash |
21-1681 21 days ago |
21-53859 21 days ago |
36-58925 36 days |
| 38373 |
Nicola9Falciola author:Nicola9Falciola |
feat (Algebra/FreeAbelianGroup /Finsupp) : The support of non zero element in a freeabeliangroup is non empty |
Add the lemma that for a nonzero a : FreeAbelianGroup X the support of it is non empty.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
3/0 |
Mathlib/Algebra/FreeAbelianGroup/Finsupp.lean |
1 |
7 |
['Nicola9Falciola', 'SnirBroshi', 'github-actions'] |
ocfnash assignee:ocfnash |
21-1673 21 days ago |
36-43816 36 days ago |
37-32026 37 days |
| 39162 |
anovickis author:anovickis |
feat(Topology/PartitionOfUnity): add pointwise_decomposition_finsum + companions |
Add three short lemmas to `Mathlib/Topology/PartitionOfUnity.lean` extending the existing `PartitionOfUnity` API:
- `pointwise_decomposition_finsum` — for `f : X → ℝ` and `x ∈ s`, `f x = ∑ᶠ i, ρ i x · f x`. This is the pointwise step that lifts to integral linearity in measure-theoretic PoU integration: `∫_s f dμ = ∑ᶠ i, ∫_s (ρ i · f) dμ`.
- `one_minus_sum_nonneg` — `0 ≤ 1 - ∑ᶠ i, ρ i x`. Direct rearrangement of the existing `sum_le_one` field; useful as a complement-mass remainder bound in chart-by-chart estimates.
- `abs_le_one` — `|ρ i x| ≤ 1`. Combines the existing `nonneg` and `le_one`; convenience for absolute-value bounds.
All three are short proofs using existing structure fields (`sum_eq_one`, `sum_le_one`, `nonneg`, `le_one`).
These came up while writing chart-by-chart Stokes-on-manifold estimates where one wants to decompose `∫_M f` into chart-supported pieces using a partition of unity. The pointwise identity is the obvious first step; the other two are complementary algebraic bounds that show up in remainder estimates.
---
🤖 Generated with [Claude Code](https://claude.com/claude-code) |
t-topology
new-contributor
LLM-generated
|
27/0 |
Mathlib/Topology/PartitionOfUnity.lean |
1 |
2 |
['github-actions'] |
urkud assignee:urkud |
18-1646 18 days ago |
18-83967 18 days ago |
18-83736 18 days |
| 39239 |
alainchmt author:alainchmt |
feat(FieldTheory/Finite): irreducible polynomial divides X^q^n - X iff degree divides n |
---
Add the theorem saying that, for an irreducible polynomial `f` over a finite field `K`, the degree of `f` divides `n` if and only if `f` divides `X ^ (Nat.card K) ^ n - X`. Include auxiliary lemmas.
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
34/0 |
Mathlib/FieldTheory/Finite/Extension.lean,Mathlib/FieldTheory/Minpoly/Field.lean |
2 |
2 |
['github-actions'] |
nobody |
17-57219 17 days ago |
17-57308 17 days ago |
17-57077 17 days |
| 39279 |
jayscambler author:jayscambler |
feat(Cryptography/Sigma): Schnorr sigma protocol and signature scheme |
Adds `Mathlib/Cryptography/Sigma/Schnorr.lean`. New file in a new top-level directory; mathlib currently has no `Mathlib/Cryptography/`, so I've taken `Mathlib/Cryptography/Sigma/` as the natural home for sigma-protocol formalizations.
The file proves the three defining properties of Schnorr's identification scheme as a sigma protocol:
- `Schnorr.correct`: completeness. Honest verifier accepts honest signer's transcript.
- `Schnorr.specialSoundness`: from two accepting transcripts sharing the commitment but using different challenges `c, c'`, the witness `x = (s - s') / (c - c')` is recovered. Needs `q` prime so `c - c'` is invertible in `ZMod q`.
- `Schnorr.hvzkAccepts`: the HVZK simulator `g^s · (y^c)⁻¹` always yields accepting transcripts. This is the structural-correctness half of HVZK only; the distributional indistinguishability statement is a separate result and not in this PR.
On top of the sigma protocol there's `Schnorr.Signature.{keyGen, sign, verify, correct}` wrapping it as a Fiat-Shamir signature scheme; `Schnorr.Signature.correct` is a one-line corollary of `Schnorr.correct`.
Two auxiliary lemmas, `Schnorr.gpow_sub` and `Schnorr.gpow_mul`, bridge `ZMod q` arithmetic and group exponentiation under `Fintype.card G = q`. They're local to this file for now because the surrounding `gpow` API is itself cryptography-specific; if a general `ZMod q`-graded group action framework lands in mathlib later, both lemmas would become instances of it.
There's also a small `example` instantiating everything on `Multiplicative (ZMod q)` for `Fact q.Prime` to show the API typechecks. That instantiation is a toy (DLOG is trivial in that group), but it confirms the abstraction is usable.
**AI disclosure**: this PR was a collaboration between myself, Grey Haven's autocontext and Claude Opus 4.7 (Anthropic). I read each line and built locally on current master. (strawberry has three r's) |
new-contributor
LLM-generated
|
352/0 |
Mathlib.lean,Mathlib/Cryptography/Sigma/Schnorr.lean |
2 |
2 |
['github-actions'] |
nobody |
16-34661 16 days ago |
16-34740 16 days ago |
16-34999 16 days |
| 38114 |
javgomzar author:javgomzar |
feat(FinitelyPresentedGroup): add finite groups instance |
Add IsFinitelyPresented instance for finite groups.
Co-authored-by: Hang Lu Su , Thomas Browning
---
[](https://gitpod.io/from-referrer/)
|
t-group-theory
new-contributor
large-import
|
31/2 |
Mathlib/GroupTheory/FinitelyPresentedGroup.lean,Mathlib/GroupTheory/FreeGroup/Basic.lean |
2 |
33 |
['github-actions', 'javgomzar', 'kbuzzard', 'mathlib-merge-conflicts', 'plp127', 'tb65536', 'vihdzp'] |
mattrobball assignee:mattrobball |
16-26271 16 days ago |
16-26307 16 days ago |
39-23813 39 days |
| 37928 |
AlexeyMilovanov author:AlexeyMilovanov |
refactor(Computability.Encoding): unbundle Γ and remove FinEncoding |
This PR unbundles the alphabet `Γ` from the `Encoding` structure and completely removes `FinEncoding`.
`Encoding`: The alphabet `Γ` is now an explicit parameter: `structure Encoding (α : Type u) (Γ : Type v)`.
`FinEncoding`: Removed. Finiteness is now handled via standard typeclasses (e.g., `[Fintype Γ] (e : Encoding α Γ)`).
Combinators: Functions like `finEncodingPair` are simplified to `encodingPair`, dropping the `fin` prefix and `[Fintype]` requirements where no longer needed.
Downstream: Mechanically updated `Mathlib.Computability` and `Mathlib.ModelTheory` to pass the explicit `Γ` and use `[Fintype Γ]` where `FinEncoding` was previously required.
|
new-contributor
maintainer-merge
|
87/67 |
Mathlib/Computability/Encoding.lean,Mathlib/ModelTheory/Encoding.lean |
2 |
9 |
['AlexeyMilovanov', 'dagurtomas', 'github-actions', 'vihdzp'] |
nobody |
16-6132 16 days ago |
22-57110 22 days ago |
48-36735 48 days |
| 39341 |
drocta author:drocta |
feat(Algebra/Colimit/DirectLimit): add DirectLimit.(NonUnital)StarAlgebra.(lift/of) maps and associated lemmas |
add the `of` and `lift` maps for `DirectLimit.StarAlgebra` and `DirectLimit.NonUnitalStarAlgebra`, as well as the associated lemmas, `of_f`, `lift_comp_of`, `lift_of`, and `hom_ext` for each. Also make `DirectLimit.NonUnitalAlgebra` only require `[Monoid R]` rather than `[CommSemiring R]`.
---
Use of AI: I again asked ChatGPT for some advice about some things about this code. I can personally vouch for all of the code I'm submitting, and that I understand all of it.
This is the third part of my project towards supporting direct limits of $C^∗$ -algebras (as I described [on Zulip](https://leanprover.zulipchat.com/#narrow/channel/113489-new-members/topic/Early.20feedback.20on.20approach.20towards.20formalizing.20UHF.20algebras.3F) ).
This PR adds an import of `Mathlib.Algebra.Star.StarAlgHom` (because it needs `StarAlgHom` and `NonUnitalStarAlgHom`) replacing/encompassing the previously added imports of `Mathlib.Algebra.Star.StarRingHom` and `Mathlib.Algebra.Algebra.NonUnitalHom` (added in PR #38308 and #38672 respectively). |
t-algebra
new-contributor
label:t-algebra$ |
100/3 |
Mathlib/Algebra/Colimit/DirectLimit.lean |
1 |
2 |
['github-actions'] |
nobody |
16-684 16 days ago |
16-3376 16 days ago |
16-3145 16 days |
| 39392 |
jayscambler author:jayscambler |
feat(Cryptography): one-time pad and Shannon perfect secrecy |
Adds `Mathlib/Cryptography/OTP.lean`. One-time pad over an arbitrary
finite abelian group `G`:
- `OTP.encrypt k m := m + k`, `OTP.decrypt k c := c - k`.
- `OTP.correct`: `decrypt k (encrypt k m) = m`, by `abel`.
- `OTP.perfect_secrecy`: for any `m₀, m₁`, the distributions of
`encrypt k m₀` and `encrypt k m₁` over uniform `k` are equal;
both reduce to `PMF.uniformOfFintype G`. Proof goes via
`Equiv.addLeft`.
Independent of the Schnorr PR (#39279); no shared definitions. Unlike
everything else likely to live under `Mathlib/Cryptography/`, the
security guarantee here is information-theoretic, not computational.
**AI disclosure**: this PR was a collaboration between myself, Grey
Haven's autocontext and Claude Opus 4.7 (Anthropic). I read each
line and built locally on current master. (strawberry has three r's) |
new-contributor
LLM-generated
|
76/0 |
Mathlib.lean,Mathlib/Cryptography/OTP.lean |
2 |
3 |
['MrBrain295', 'github-actions'] |
nobody |
14-83613 14 days ago |
15-19687 15 days ago |
15-19456 15 days |
| 37707 |
MavenRain author:MavenRain |
feat(Combinatorics/SimpleGraph): add IsMaximalClique/IsMaximalIndepSet, refactor IsMaximum* to MaximalFor |
Addresses #34962
|
new-contributor
t-combinatorics
|
63/31 |
Mathlib/Combinatorics/SimpleGraph/Clique.lean |
1 |
6 |
['MavenRain', 'SnirBroshi', 'eric-wieser', 'github-actions'] |
nobody |
13-67336 13 days ago |
13-67408 13 days ago |
13-68817 13 days |
| 37720 |
cjrl author:cjrl |
feat(Data/Fintype/Card): existsUnique_notMem_image_of_injective_of_card_succ |
This pull requests adds a small theorem `existsUnique_notMem_image_of_injective_of_card_succ` to `Mathlib/Data/Fintype/Card` that says given an injective map f : α → β such that β has cardinality one more than α, there exists a unique element of β not in the image of f.
This can be viewed as going in the opposite direction of `card_lt_of_injective_of_notMem`.
This little fact is needed for our Latin Square PR #36698.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
t-set-theory
|
19/0 |
Mathlib/Data/Finset/Card.lean,Mathlib/Data/Fintype/Card.lean |
2 |
10 |
['IvanRenison', 'cjrl', 'dagurtomas', 'ghseeli', 'github-actions'] |
nobody |
12-84316 12 days ago |
12-84316 12 days ago |
50-54941 50 days |
| 26479 |
thefundamentaltheor3m author:thefundamentaltheor3m |
feat(Analysis/Complex/CauchyIntegral): Cauchy–Goursat for Unbounded Rectangles |
In this PR, we prove versions of the Cauchy-Goursat theorem where the contours in question are rectangular and unbounded (ie, where the contours look like the $\bigsqcup$ symbol). I am not sure if I have formalised these in the best way, or if `Analysis.Complex.CauchyIntegral` is the best place for them (it might be prudent to reorganise the file into multiple files at some point), but I believe this is a useful result. Suggestions welcome.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-analysis
sphere-packing
|
219/0 |
Mathlib/Analysis/Complex/CauchyIntegral.lean |
1 |
7 |
['github-actions', 'j-loreaux', 'loefflerd', 'mathlib4-merge-conflict-bot', 'thefundamentaltheor3m', 'wwylele'] |
urkud assignee:urkud |
11-75151 11 days ago |
11-75151 11 days ago |
45-86142 45 days |
| 35122 |
Marygold-Dusk author:Marygold-Dusk |
feat: define C^n submersions |
This PR defines submersions between C^n manifolds. In the infinite-dimensional setting, submersions are defined via local normal forms rather than surjectivity of the mfderiv. A map f is a submersion at x if, in suitable charts around x and f x, it has the form (u, v) ↦ u after identifying the model space with a product.
We prove a few basic properties:
- being a submersion is a local property,
- products of submersions are submersions,
- the set of submersed points is open
Future PRs will prove that submersions are C^n and deduce equivalence with the standard definition in finite dimensions. From the path towards the regular value theorem.
This file was developed under the supervision of Michael Rothgang.
Co-authored-by: Michael Rothgang
---
Most of the design is analogues to immersions.
|
t-differential-geometry
new-contributor
|
642/0 |
Mathlib.lean,Mathlib/Geometry/Manifold/Submersion.lean,docs/references.bib |
3 |
54 |
['Marygold-Dusk', 'chrisflav', 'github-actions', 'grunweg'] |
PatrickMassot and grunweg assignee:grunweg assignee:PatrickMassot |
11-63339 11 days ago |
11-63339 11 days ago |
55-83642 55 days |
| 39269 |
godofecht author:godofecht |
feat(Algebra/Spectrum): add the second resolvent identity |
Adds `spectrum.resolvent_sub_resolvent`:
For `a b : A` in an `R`-algebra and `r` in the resolvent set of both,
`resolvent a r - resolvent b r = resolvent a r * (a - b) * resolvent b r`.
Companion to `spectrum.resolvent_eq`. |
t-algebra
new-contributor
label:t-algebra$ |
15/0 |
Mathlib/Algebra/Algebra/Spectrum/Basic.lean |
1 |
3 |
['github-actions', 'wwylele'] |
nobody |
11-33133 11 days ago |
17-21298 17 days ago |
17-21067 17 days |
| 39366 |
akiezun author:akiezun |
feat(Data/Nat): add prime divisibility for ascFactorial and choose |
Adds two prime-divisibility lemmas for natural-number factorial/binomial APIs.
The first characterizes when a prime divides an ascending factorial:
`Nat.Prime.dvd_ascFactorial_iff`.
The second applies this to binomial coefficients:
`Nat.Prime.dvd_choose_add_sub_one_iff`, using
`Nat.ascFactorial_eq_factorial_mul_choose'` and cancellation of the `n!` factor
when `n < p`.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
large-import
|
46/0 |
Mathlib.lean,Mathlib/Data/Nat/Choose/Consecutive.lean,Mathlib/Data/Nat/Factorial/BigOperators.lean |
3 |
9 |
['SnirBroshi', 'akiezun', 'github-actions', 'wwylele'] |
nobody |
11-25680 11 days ago |
11-27721 11 days ago |
15-37869 15 days |
| 29744 |
espottesmith author:espottesmith |
feat(Combinatorics): define directed hypergraphs |
This PR defines directed hypergraphs:
```
@[ext]
structure DiHypergraph (α : Type*) where
/-- The vertex set -/
vertexSet : Set α
/-- The edge set -/
edgeSet : Set ((Set α) × (Set α))
/-- Each edge is a pair (s, d), where s ⊆ vertexSet and d ⊆ vertexSet -/
edge_src_dst_isSubset_vertexSet' : ∀ ⦃e⦄, e ∈ edgeSet → e.1 ⊆ vertexSet ∧ e.2 ⊆ vertexSet
```
Additional definitions:
- tail/head stars and negative/positive stars
- some special cases (B-Graph, F-Graph, BF-Graph, and what I'm calling a "non-endless" dihypergraph, where neither the source/tail nor the destination/head are empty)
- Vertex and (hyper)edge adjacency
- isolated vertices
- empty and nonempty dihypergraphs
The design employed here is based off of #28613, but this PR does not depend on that one.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
398/0 |
Mathlib.lean,Mathlib/Combinatorics/DiHypergraph/Basic.lean |
2 |
4 |
['b-mehta', 'espottesmith', 'github-actions', 'mathlib4-merge-conflict-bot'] |
nobody |
11-2543 11 days ago |
56-58328 56 days ago |
114-41564 114 days |
| 39567 |
AlexBrodbelt author:AlexBrodbelt |
feat(Mathlib/Data/Finite/Option): option type is finite iff type is finite |
Option type is finite if and only if the type is finite.
This is an intermediate result to proving that if the `GroupWithZero` is (in)finite then the `Units` are (in)finite.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
|
25/0 |
Mathlib.lean,Mathlib/Data/Finite/Option.lean |
2 |
11 |
['AlexBrodbelt', 'github-actions', 'plp127', 'themathqueen'] |
nobody |
10-40215 10 days ago |
10-56266 10 days ago |
10-56649 10 days |
| 37350 |
aditya-ramabadran author:aditya-ramabadran |
feat(Analysis/Distribution): define canonical maps between Schwartz/test functions, distributions/tempered distributions |
Defines these canonical maps: (1) continuous linear map from $\mathcal D$ to $\mathcal S$, and (2) induced (linear) restriction map from $\mathcal S'$ to $\mathcal D'$, as assigned by @ADedecker.
---
Put in a separate file since Distribution.lean only imports TestFunction right now and I thought it was cleaner to do in a new bridge file with both the maps. Open to changing this though.
* Made use of #36445 (proved first map locally on fixed support spaces first by local seminorm estimates, then used limitCLM)
* Needed a real to complex bridge `TestFunction.ToComplexSchwartzMap` since distributions are defined on real-valued test functions but tempered distributions in mathlib are defined on complex-valued Schwartz functions
* Induced map $\mathcal S'(E,F) \to \mathcal D'(Ω,F)$ is $\mathbb C$-linear
The main important defs are `ContDiffMapSupportedIn.toSchwartzMapCLM` which is the local fixed-support part, then `TestFunction.toSchwartzMapCLM` (where the continuity uses limitCLM to glue the local continuous linear maps on each $\mathcal D_K$), and `TemperedDistribution.toDistributionLM` which is the linear map from tempered distributions to ordinary distributions.
Tested with `lake env lean Mathlib/Analysis/Distribution/TestFunctionSchwartz.lean`
[](https://gitpod.io/from-referrer/)
|
t-analysis
new-contributor
|
225/0 |
Mathlib.lean,Mathlib/Analysis/Distribution/TestFunctionSchwartz.lean |
2 |
24 |
['aditya-ramabadran', 'github-actions', 'j-loreaux'] |
ADedecker and mcdoll assignee:mcdoll assignee:ADedecker |
10-32174 10 days ago |
19-37348 19 days ago |
51-37413 51 days |
| 34713 |
dennj author:dennj |
feat(Probability/Markov): stationary distributions for stochastic matrices |
This PR proves that every row-stochastic matrix on a finite nonempty
state space has a stationary distribution in the standard simplex.
Main additions to `Mathlib/Probability/Markov/Stationary.lean`:
- `IsStationary`: A distribution μ is stationary for matrix P if μ ᵥ* P = μ
- `cesaroAverage`: Cesàro average of iterates of a vector under a matrix
- `Matrix.rowStochastic.exists_stationary_distribution`: existence theorem
The proof uses Cesàro averaging: start with uniform distribution, form
averages, extract convergent subsequence by compactness, show limit is
stationary via L¹ non-expansiveness.
Also adds `vecMul_mem_stdSimplex` to `Stochastic.lean`: multiplying a
probability vector by a row-stochastic matrix preserves simplex membership.
This is human-made PR with AI help in golfing proof and documenting the code. |
new-contributor
t-measure-probability
|
166/0 |
Mathlib.lean,Mathlib/LinearAlgebra/Matrix/Stochastic.lean,Mathlib/Probability/Markov/Stationary.lean |
3 |
17 |
['EtienneC30', 'dennj', 'dupuisf', 'github-actions', 'grunweg', 'j-loreaux', 'mathlib-merge-conflicts', 'riccardobrasca'] |
kex-y assignee:kex-y |
10-1008 10 days ago |
33-9462 33 days ago |
43-42244 43 days |
| 38014 |
cduenasnavarro author:cduenasnavarro |
feat(InformationTheory): linear codes over finite fields and minimum distance properties |
Define linear codes over a finite field `F` as finite-dimensional subspaces of `Fin n → F`,
together with their minimum Hamming distance.
Main definitions:
* `LinearCode`
* `minDist`
* `LinearCodeWithDist`
* `hammingSphere`
Main results:
* `minDist_eq_sInf_pairwiseDist`: characterisation of the minimum distance via pairwise distances
* `disjoint_spheres`: Hamming spheres of radius `t` around distinct codewords are disjoint
if `2 * t < d`
Pending:
* Choosing an adequate book reference
---
[](https://gitpod.io/from-referrer/)
|
t-measure-probability
new-contributor
|
181/0 |
Mathlib.lean,Mathlib/InformationTheory/Coding/LinearCode.lean |
2 |
37 |
['cduenasnavarro', 'github-actions', 'linesthatinterlace', 'rkirov', 'vihdzp', 'wwylele'] |
kex-y assignee:kex-y |
10-1004 10 days ago |
46-20485 46 days ago |
46-21017 46 days |
| 39384 |
EngelsVon author:EngelsVon |
feat(Analysis/Calculus/DifferentialForm): Stokes' theorem on rectangular boxes |
## Summary
This PR proves the generalized Stokes theorem for differential forms on rectangular boxes $[a, b] \subset \mathbb{R}^{m+1}$.
The proof strategy is:
1. Extract the `i`-th signed face component `boxFaceComponent ω i` from an `m`-form `ω` — a scalar function whose divergence equals the top-form density of the exterior derivative `dω`.
2. Apply Mathlib's existing divergence theorem for boxes (`integral_divergence_of_hasFDerivAt_off_countable'`).
This gives a genuine proved Stokes formula in the Euclidean setting, complementing the existing infrastructure for differential forms.
## Main definitions
- `DifferentialForm.topFormDensity`: density function of a top-form field
- `DifferentialForm.boxFaceComponent`: the `i`-th signed face component of an `m`-form on `ℝ^(m+1)`
- `DifferentialForm.boxBoundaryIntegral`: the signed boundary integral over `∂[a,b]`
## Main results
- `box_stokes_of_hasFDerivAt`: Stokes' theorem on boxes with pointwise differentiability hypotheses
- `box_stokes_of_contDiff`: a convenient `C¹` formulation
|
t-analysis
new-contributor
|
314/0 |
Mathlib.lean,Mathlib/Analysis/Calculus/DifferentialForm/BoxStokes.lean |
2 |
2 |
['github-actions'] |
j-loreaux assignee:j-loreaux |
10-995 10 days ago |
15-28060 15 days ago |
15-27829 15 days |
| 39389 |
i-love-lean author:i-love-lean |
feat(Analysis/SpecialFunctions): homeomorphism for spherical coordinates |
A few months ago, I noticed that mathlib was missing change of variables to spherical coordinates, which is taught in undergraduate calculus and useful for many 3D integrals. So far, I used `PolarCoord.lean` as reference and implemented a similar homeomorphism for spherical coordinates. There's still a lot of work left to prove an analog of `integral_comp_polarCoord_symm` but for spherical coordinates, so I'm splitting up the work into several PRs. I also fixed a typo in `PolarCoord.lean`. |
t-analysis
new-contributor
|
133/2 |
Mathlib.lean,Mathlib/Analysis/SpecialFunctions/Complex/Arg.lean,Mathlib/Analysis/SpecialFunctions/PolarCoord.lean,Mathlib/Analysis/SpecialFunctions/SphericalCoord.lean |
4 |
4 |
['github-actions', 'i-love-lean', 'wwylele'] |
j-loreaux assignee:j-loreaux |
10-994 10 days ago |
15-19195 15 days ago |
15-19784 15 days |
| 39406 |
roos-j author:roos-j |
feat(Analysis): van der Corput's lemma |
Adds van der Corput's lemma on one-dimensional oscillatory integrals, a standard tool in harmonic analysis.
Co-authored-by: Manasa Praveen
---
From https://github.com/roos-j/lean-oscillatory, see there for future plans
Zulip discussion [#mathlib4 > Oscillatory integrals in Lean](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Oscillatory.20integrals.20in.20Lean/with/584786060)
AI disclosure: The code in this PR was predominantly human-written. gpt-5.5 has helped in the later stages with shortening proofs, golfing and general advice.
|
t-analysis
new-contributor
|
551/0 |
Mathlib.lean,Mathlib/Analysis/OscillatoryIntegrals/VanDerCorput.lean |
2 |
2 |
['github-actions'] |
j-loreaux assignee:j-loreaux |
10-992 10 days ago |
14-65054 14 days ago |
14-65887 14 days |
| 39605 |
Qinghev author:Qinghev |
Add docstrings for reversed range telescoping lemmas |
This PR adds docstrings for two existing Finset telescoping lemmas and their additive versions generated by `to_additive`:
* `Finset.prod_range_div'` / `Finset.sum_range_sub'`
* `Finset.eq_prod_range_div` / `Finset.eq_sum_range_sub`
The goal is a small documentation-only contribution that makes the reversed range telescoping API easier to discover from search and hover docs.
Local checks:
* `git diff --check -- Mathlib/Algebra/BigOperators/Group/Finset/Basic.lean`
* Attempted `lake env lean Mathlib/Algebra/BigOperators/Group/Finset/Basic.lean`, but local validation is currently blocked by downloading the `leanprover/lean4:v4.30.0-rc2` toolchain from GitHub timing out/connection-resetting on this machine.
Opened as draft until the toolchain/network check can be completed or CI confirms the documentation-only change.
|
t-algebra
new-contributor
label:t-algebra$ |
8/2 |
Mathlib/Algebra/BigOperators/Group/Finset/Basic.lean |
1 |
2 |
['github-actions'] |
nobody |
9-50497 9 days ago |
9-50497 9 days ago |
9-50266 9 days |
| 39332 |
Michaillus author:Michaillus |
chore(Topology/Spectral): Added two small lemmas |
chore(Topology/Spectral): Added two lemmas
`IsCompact.isClosed_constructibleTopology_of_isOpen`
`IsCompact.isClosed_constructibleTopology_of_isClosed`
---
[](https://gitpod.io/from-referrer/)
|
t-topology
new-contributor
|
12/0 |
Mathlib/Topology/Spectral/ConstructibleTopology.lean |
1 |
7 |
['Michaillus', 'github-actions', 'plp127', 'qawbecrdtey'] |
PatrickMassot assignee:PatrickMassot |
9-46991 9 days ago |
16-15067 16 days ago |
16-14836 16 days |
| 39225 |
junodeveloper author:junodeveloper |
feat(SimpleGraph): add no-bridge theorem for even degree graphs |
This PR proves that a finite graph in which every vertex has even degree has no bridge.
It adds:
* `SimpleGraph.not_isBridge_of_even_degree`
The proof argues by contradiction: if an edge is a bridge, delete it and look at the connected component containing one endpoint. In that component, the endpoint has odd degree, while any other odd-degree vertex would contradict the bridge assumption and the even-degree hypothesis. This contradicts the handshaking lemma via the existing odd-degree API.
Local checks:
```bash
lake build Mathlib.Combinatorics.SimpleGraph.Connectivity.EdgeConnectivity
lake exe lint-style Mathlib.Combinatorics.SimpleGraph.Connectivity.EdgeConnectivity
lake exe runLinter Mathlib.Combinatorics.SimpleGraph.Connectivity.EdgeConnectivity
```
## AI usage disclosure
I used OpenClaw/Codex while developing this PR. Much of the Lean proof of `not_isBridge_of_even_degree` was drafted with AI assistance, including API search and proof refactoring. I reviewed the generated code, made edits, ran the local checks above, and understand and take responsibility for the final statement and proof. |
t-combinatorics
new-contributor
large-import
LLM-generated
|
122/0 |
Mathlib/Combinatorics/SimpleGraph/Connectivity/EdgeConnectivity.lean |
1 |
12 |
['Rida-Hamadani', 'SnirBroshi', 'github-actions', 'junodeveloper', 'linesthatinterlace'] |
nobody |
9-41762 9 days ago |
18-11337 18 days ago |
18-11106 18 days |
| 39607 |
TentativeConvert author:TentativeConvert |
feat(Algebra/DirectSum): equivalence between direct sum indexed by ι₁ and double sum indexed by ι₂ and fibres of f : ι₁ → ι₂ |
1. Add variant `equivCongrLeft'` of `equivCongrLeft`, and corresponding `…_apply` lemma.
2. Add `…_of lemmas` for both `equivCongrLeft` and `equivCongrLeft'`.
3. Add `…of lemma` for `sigmaCurry`, i.e. `sigmaCurry_of`.
4. Add `sigmaFiberAddEquiv`: the equivalence between a direct sum indexed by a type `ι₁` and the double sum indexed by a type `ι₂` and the fibres of a map `f : ι₁ → ι₂`. Add two `…_apply` lemmas and an `…_of` lemma.
---
This is supposed to be a first step towards merging the draft PR #39356.
re 1: Mathematically, I don't see why one version should be preferred over the other, but I found the existing `equivCongrLeft` more difficult to work with when the equivalence `h : ι ≃ κ` is naturally given in the opposite direction. (I could not avoid explicit type casts through the equality `h.symm.symm = h` when defining `sigmaFiberAddEquiv` in terms of `equivCongrLeft`.)
Very unsure about the name of `equivCongrLeft'`. (I see that the name `equivCongrLeft` was chosen in analogy with `Equiv.piCongrLeft`. `Equiv.piCongrRight` looks very different, so presumably `equivCongrLeft'` should *not* be called `equivCongrRight`.)
re 4: Very unsure about the naming of the two different `…_apply` lemmas; called them `…_apply` and `…_apply'` for now. The second (`…_apply'`) cannot be a `simp` lemma as it would prevent the first (`…_apply`) from firing.
I've used Claude Opus for understanding error messages and git interaction, but everything is hand coded.
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
66/1 |
Mathlib/Algebra/DirectSum/Basic.lean |
1 |
3 |
['github-actions'] |
nobody |
9-41032 9 days ago |
9-53585 9 days ago |
9-54984 9 days |
| 33714 |
idontgetoutmuch author:idontgetoutmuch |
feat(Mathlib/Geometry/Manifold): Riemannian metrics exist II |
Supersedes https://github.com/leanprover-community/mathlib4/pull/33519
---
[](https://gitpod.io/from-referrer/)
|
t-differential-geometry
new-contributor
|
723/0 |
Mathlib.lean,Mathlib/Algebra/BigOperators/Finprod.lean,Mathlib/Geometry/Manifold/ExistsRiemannianMetric.lean,Mathlib/Geometry/Manifold/PartitionOfUnity.lean |
4 |
200 |
['Rida-Hamadani', 'github-actions', 'grunweg', 'idontgetoutmuch'] |
nobody |
9-2541 9 days ago |
40-42092 40 days ago |
85-48844 85 days |
| 39474 |
emlis42 author:emlis42 |
feat(Topology/Separation/Hausdorff): add `Filter.limUnder_congr` |
This PR adds `Filter.limUnder_congr` and some lemmas about `limUnder`.
`Filter.limUnder_congr` allows rewriting `limUnder` expressions using equivalences of convergence behavior, without proving the filters actually converge, allowing convergence proofs to be carried out on more convenient expressions latter. |
t-topology
new-contributor
large-import
|
24/1 |
Mathlib/Order/Filter/AtTopBot/Archimedean.lean,Mathlib/Topology/Separation/Hausdorff.lean |
2 |
2 |
['github-actions'] |
PatrickMassot assignee:PatrickMassot |
9-953 9 days ago |
13-22383 13 days ago |
13-22152 13 days |
| 38319 |
Zetetic-Dhruv author:Zetetic-Dhruv |
feat(Combinatorics/SetFamily): Assouad's dual VC bound |
Adds the Finset-level form of Assouad's 1983 dual VC bound: if a family
`𝒜 : Finset (Finset α)` has VC dimension at most `d`, then for any
ground set `X : Finset α` the dual family
`{𝒜.filter (· ∋ x) : x ∈ X}` has VC dimension at most `2 ^ (d + 1) - 1`.
New declarations (in `Finset` namespace):
- `dualFamily 𝒜 X`: for each `x ∈ X`, the subfamily `{A ∈ 𝒜 | x ∈ A}`
- `mem_dualFamily` (`@[simp]`): membership characterisation
- `exists_shatters_of_dualFamily_shatters`: Assouad's bitstring-coding lemma
- `vcDim_dualFamily_le`: the headline VC bound
Proof by Assouad's classical bitstring-coding argument. Sits on top of `Finset.shatterer` / `Finset.vcDim` from
`Mathlib.Combinatorics.SetFamily.Shatter`.
References:
- P. Assouad, Densite et dimension, Ann. Inst. Fourier 33(3) (1983), Thm 2.13
- J. Matousek, Lectures on Discrete Geometry, GTM 212, Springer, 2002, Section 10.3 Lemma 10.3.3
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
199/0 |
Mathlib.lean,Mathlib/Combinatorics/SetFamily/DualVC.lean,docs/references.bib |
3 |
37 |
['Shreyas4991', 'YaelDillies', 'Zetetic-Dhruv', 'github-actions'] |
nobody |
8-32928 8 days ago |
20-15161 20 days ago |
36-61979 36 days |
| 36667 |
NoneMore author:NoneMore |
feat(ModelTheory): add `exClosure` definition for first-order formulas |
Prepare for moving realizations between elementarily equivalent structures.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-logic
|
37/0 |
Mathlib/ModelTheory/Semantics.lean,Mathlib/ModelTheory/Syntax.lean |
2 |
2 |
['github-actions'] |
nobody |
8-2540 8 days ago |
75-73161 75 days ago |
75-72930 75 days |
| 39687 |
TentativeConvert author:TentativeConvert |
feat(Algebra/Group/Submonoid): type class to indicate that supremum in a SubmonoidClass agrees with supremum of submonoids |
Add a type class `SubmonoidClass.IsConcreteSSup` to indicate that the canonical map `.ofClass` from a class `S` of submonoids of `M` to `Submonoid M` preserves suprema.
---
This PR implements the minimal type class assumption needed to make „pushfoward of gradings along maps of indexing sets“ – see draft PR #39356 – work in some `SetLike` generality.
Given `{S M : Type*} [SetLike S M] [Monoid M] [SubmonoidClass S M]`, we have canonical maps
```
S → Submonoid M → Set M
```
The first is `Submonoid.ofClass`, the second and the composition are `coe` maps coming from the `SetLike` structures. Depending on `S`, these maps may or may not satisfy various properties with respect the lattice structures on `Submonoid M` and `Set M`. Mathlib so far includes the type class `[IsConcreteLE S M]`, which asserts that the composition `S → Set M` is order-preserving and order-reflecting. The type class defined here asserts that the first map, `S → Submonoid M`, preserves suprema.
In examples such as `S = Subgroup M`, `S = Submodule R M`, much more is true – in these cases, `S` is a complete sublattice of `Submonoid M`. But there are also examples where only the weaker property defined here holds, e.g. `S = OpenSubgroup M` for a topological group `M`.
Note on `outParam`: I did *not* write `(M : outParam Type*)` in the assumptions of `SubmonoidClass.IsConcreteSSup` in accordance with the [DocString of `Setlike`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Data/SetLike/Basic.html#SetLike). However, we do have `(B : outParam Type*)` in the definition of `IsConcreteLE`, so perhaps I'm misinterpreting the DocString.
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-algebra
label:t-algebra$ |
56/0 |
Mathlib.lean,Mathlib/Algebra/Group/Submonoid/SSup.lean |
2 |
2 |
['github-actions'] |
nobody |
7-57334 7 days ago |
7-57403 7 days ago |
7-57772 7 days |
| 37718 |
SabrinaJewson author:SabrinaJewson |
feat(Order): add conversions from `Std` order typeclasses to Mathlib ones |
`{Preorder, PartialOrder, LinearOrder}.ofStd` exist to facilitate convenient translation from `Std` order typeclasses to Mathlib ones.
The design is modelled closely after [`Init.Data.Order.PackageFactories`](https://leanprover-community.github.io/mathlib4_docs/Init/Data/Order/PackageFactories.html) (`Std.PreorderPackage` is equivalent-ish to Mathlib’s `Preorder`, and same for partial and linear orders). The `OfStdArgs` types allow conveniently bundling a whole bunch of default arguments together in a way that allows one default argument set to `extends` another.
---
[](https://gitpod.io/from-referrer/)
|
t-order
new-contributor
maintainer-merge
|
391/0 |
Mathlib.lean,Mathlib/Order/Std.lean,MathlibTest/OrderOfStd.lean |
3 |
9 |
['SabrinaJewson', 'YaelDillies', 'github-actions'] |
YaelDillies assignee:YaelDillies |
7-17651 7 days ago |
8-9447 8 days ago |
53-3558 53 days |
| 39697 |
sorrachai author:sorrachai |
feat(Data/Tree/Basic): add Membership instance, new notation, rename Tree |
Summary:
1. [Rename]([#CSLib > Splay tree PR: BinaryTree vs Tree @ 💬](https://leanprover.zulipchat.com/#narrow/channel/513188-CSLib/topic/Splay.20tree.20PR.3A.20BinaryTree.20vs.20Tree/near/596482765)) from Tree to BinaryTree, which propagates the changes to other files that use it.
2. Add membership instance, prove decidability of membership.
3. Add toListInOrder, toListPreOrder, toListPostOrder
Suggestion based on the discussion in the cslib [thread](https://leanprover.zulipchat.com/#narrow/channel/513188-CSLib/topic/Splay.20tree.20PR/near/596568391)[#CSLib > Splay tree PR @ 💬](https://leanprover.zulipchat.com/#narrow/channel/513188-CSLib/topic/Splay.20tree.20PR/near/596568391).
---
* depends on: #39707 |
new-contributor |
187/75 |
Mathlib/Combinatorics/Enumerative/Catalan/Tree.lean,Mathlib/Combinatorics/Enumerative/DyckWord.lean,Mathlib/Data/Tree/Basic.lean,Mathlib/Data/Tree/Get.lean,Mathlib/Data/Tree/Traversable.lean,Mathlib/Tactic/CancelDenoms/Core.lean,docs/overview.yaml |
7 |
4 |
['eric-wieser', 'github-actions', 'sorrachai'] |
nobody |
7-10666 7 days ago |
7-42226 7 days ago |
7-44050 7 days |
| 35069 |
A-M-Berns author:A-M-Berns |
feat(Geometry/Polygon): simple polygons and boundary map |
This PR introduces Simple polygons with the predicate `IsSimple`, which captures the idea of a non-self-intersecting boundary, in the file Simple.lean. In the file Boundary.lean, a boundary map from `AddCircle n` is defined. I prove that the range of this map is the boundary and that this map is injective if and only if the polygon is simple. I kept Boundary.lean and Simple.lean separate because future results will include stuff just about the boundary map independent of simplicity (e.g. that it is continuous in the appropriate setting) and stuff just about simple polygons independent of the boundary map (e.g. that for n = 3, IsSimple iff HasNondegenerateVertices.) I used Claude Code to help generate some of the proof material, but I golfed and edited all AI contribution.
- [x] depends on: #34598
---
|
new-contributor
t-euclidean-geometry
LLM-generated
|
360/0 |
Mathlib.lean,Mathlib/Geometry/Polygon/Boundary.lean,Mathlib/Geometry/Polygon/Simple.lean,Mathlib/Logic/Equiv/Fin/Rotate.lean |
4 |
30 |
['A-M-Berns', 'eric-wieser', 'github-actions', 'joneugster', 'jsm28', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'vihdzp', 'wwylele'] |
nobody |
7-2543 7 days ago |
93-28398 93 days ago |
95-62453 95 days |
| 35402 |
samueloettl author:samueloettl |
feat(Dynamics/BirkhoffSum): birkhoffAverage const |
---
I think this is useful and one of these should be a simp lemma.
I'm not really sure if I got the naming of the theorems correct.
When generalizing to the assumption (n : R) ≠ 0 instead of the special case CharZero R with n ≠ 0 I had to use "open Classical in". I'm a bit unfamiliar with that part so please check if this makes sense. See also https://github.com/leanprover-community/mathlib4/pull/35307#discussion_r2823586252
[](https://gitpod.io/from-referrer/)
|
t-dynamics
new-contributor
|
14/0 |
Mathlib/Dynamics/BirkhoffSum/Average.lean |
1 |
26 |
['Maldooor', 'github-actions', 'lua-vr', 'mcdoll', 'samueloettl'] |
sgouezel assignee:sgouezel |
7-1369 7 days ago |
30-41892 30 days ago |
96-40474 96 days |
| 39518 |
abeldonate author:abeldonate |
feat(RingTheory/LocalProperties/Projective): Projective Module theorem |
Theorem: R Noetherian, M finitely generated R-Mod. Then:
M projective iff M_m free for all m maximal
|
t-ring-theory
new-contributor
large-import
|
21/0 |
Mathlib/RingTheory/LocalProperties/Projective.lean |
1 |
9 |
['abeldonate', 'github-actions', 'mbkybky', 'vlad902'] |
nobody |
6-63458 6 days ago |
10-41077 10 days ago |
10-83101 10 days |
| 39530 |
RaggedR author:RaggedR |
feat(Combinatorics/SimpleGraph): group actions on simple graphs |
This adds the first connection between Mathlib's MulAction and SimpleGraph libraries. The GraphAction class asserts that a group action on the vertex type preserves the adjacency relation, and builds on it to define vertex-transitivity and arc-transitivity for graphs.
The GraphAction typeclass gives adj_smul_iff (the biconditional for group actions) and toIso (each group element induces a graph automorphism). The IsVertexTransitive class combines GraphAction with IsPretransitive, and IsArcTransitive requires transitivity on ordered adjacent pairs (arcs).
The main theorem is the standard characterization: a graph is arc-transitive if and only if it is vertex-transitive and locally transitive (the stabilizer of each vertex acts transitively on its neighbors). The forward direction is proved directly by composing a vertex-transporting element with a neighbor-transporting stabilizer element. The reverse direction shows that an arc-transitive graph with no isolated vertices is vertex-transitive.
These definitions are the algebraic graph theory prerequisites for formalizing coset graphs (Sabidussi's construction) and the characterization of symmetric graphs via double cosets and involutions (Lorimer's theorem).
---
LLM tools were used to assist with Lean formalization. The mathematical content is the author's own work. |
t-combinatorics
new-contributor
LLM-generated
|
130/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Action.lean |
2 |
7 |
['RaggedR', 'b-mehta', 'github-actions', 'mathlib-bors'] |
nobody |
6-52826 6 days ago |
6-52826 6 days ago |
11-21045 11 days |
| 38194 |
ryanncode author:ryanncode |
feat(LinearAlgebra/BilinearForm): add indefinite metrics |
Add the `IndefiniteMetric` structure to support vector spaces equipped with a non-degenerate, symmetric, indefinite bilinear form.
Provide the algebraic foundation for indefinite inner product spaces by formalizing the metric via `LinearMap.BilinForm` and extracting its associated quadratic form without enforcing the `IsPosSemidef` typeclass.
Previously, mathlib required strictly positive-definite metrics to instantiate inner product spaces (`InnerProductSpace`), which prevented the formalization of indefinite geometries without causing typeclass inference failures. Bridge this gap by isolating the symmetric bilinear form from topological and positivity constraints, allowing the library to handle generalized indefinite metric spaces safely.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
47/0 |
Mathlib.lean,Mathlib/LinearAlgebra/BilinearForm/IndefiniteMetric.lean |
2 |
5 |
['dagurtomas', 'github-actions', 'mathlib-merge-conflicts', 'ryanncode'] |
nobody |
6-45026 6 days ago |
6-46771 6 days ago |
22-16309 22 days |
| 39212 |
emlis42 author:emlis42 |
feat(Algebra/ContinuedFractions): add `partNums!` and `partDens!` |
This PR adds `partNums!` and `partDens!`, which provide infinite stream representations for the sequences of partial numerators and denominators of a generalized continued fraction. |
t-algebra
new-contributor
label:t-algebra$ |
8/0 |
Mathlib/Algebra/ContinuedFractions/Basic.lean |
1 |
4 |
['emlis42', 'github-actions', 'grunweg'] |
nobody |
6-29566 6 days ago |
18-31326 18 days ago |
18-31095 18 days |
| 37716 |
slavanaprienko author:slavanaprienko |
feat(LinearAlgebra/Matrix/Determinant): Desnanot-Jacobi identity |
This PR adds the Desnanot-Jacobi identity (also known as the Lewis Carroll identity or Dodgson condensation): for any (n+2)×(n+2) matrix M over a commutative ring,
$$\det(M) \cdot \det(M_{1,n}^{1,n}) = \det(M_1^1) \cdot \det(M_n^n) - \det(M_1^n) \cdot \det(M_n^1)$$
The proof follows Bressoud's *Proofs and Confirmations* (Cambridge University Press, 1999): multiply M by an auxiliary matrix built from columns of the adjugate, then compare determinants. This yields the identity premultiplied by det(M). To cancel, we pass to a universal polynomial ring (an integral domain with nonzero determinant), then specialize back to arbitrary commutative rings.
It seems there's some interest in adding this:
https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/Determinantal.20identity.20and.20the.20Cauchy.20matrix.20determinant/with/582946873
--- |
t-algebra
new-contributor
label:t-algebra$ |
217/0 |
Mathlib.lean,Mathlib/LinearAlgebra/Matrix/Determinant/DesnanotJacobi.lean |
2 |
13 |
['SnirBroshi', 'github-actions', 'grunweg', 'kim-em', 'slavanaprienko'] |
nobody |
6-10075 6 days ago |
18-20032 18 days ago |
19-58031 19 days |
| 35753 |
Vilin97 author:Vilin97 |
feat(Topology/Algebra/Order): regular grid helpers and piecewise linear interpolation |
Make API for piecewise linear interpolation on regular grids. I need these to for ODE time-stepping methods, like forward Euler, and later Runge–Kutta methods.
Follow-up PR: #35755 (forward Euler method convergence).
I don't know if these numerical analysis ODE-solving methods even belong in mathlib. If someone could advise me on it, I would appreciate it.
---
The initial proof was produced by [Aristotle](https://aristotle.harmonic.fun). The code was iteratively refined (factoring out lemmas, golfing, simplifying proofs) using Claude Code.
- [ ] depends on: #38091 |
t-topology
new-contributor
LLM-generated
maintainer-merge
|
201/0 |
Mathlib.lean,Mathlib/Topology/Algebra/Order/PiecewiseLinear.lean |
2 |
59 |
['Vilin97', 'YanYablonovskiy', 'adomani', 'botbaki-review', 'copilot-pull-request-reviewer', 'dagurtomas', 'eric-wieser', 'github-actions', 'grunweg', 'j-loreaux', 'mathlib-dependent-issues', 'wwylele'] |
ADedecker assignee:ADedecker |
6-1036 6 days ago |
28-13263 28 days ago |
60-62112 60 days |
| 39436 |
dtumad author:dtumad |
chore: Add `seqLeft` and `seqRight` unfolding to monad_norm simp set |
This PR adds `seqLeft_eq_bind` and `seqRight_eq_bind` to `monad_norm`, so that `<*` and `*>` get unfolded in the same way as `<*>` already does when using the `simp` set.
---
[](https://gitpod.io/from-referrer/)
|
t-meta
new-contributor
|
1/1 |
Mathlib/Tactic/Attr/Core.lean |
1 |
2 |
['github-actions'] |
dwrensha assignee:dwrensha |
5-2085 5 days ago |
14-15288 14 days ago |
14-15057 14 days |
| 38214 |
emlis42 author:emlis42 |
feat(Algebra/ContinuedFractions): add Euler's continued fraction |
This PR formalizes Euler’s continued fractions by providing `Euler` which construct one by giving head term and coefficients with some basic property.
We also introduce a transformation `GenContFract.toEuler` that maps a generalized continued fraction `g : GenContFract K` to an equivalent Euler-form continued fraction. |
new-contributor
t-algebra
label:t-algebra$ |
262/0 |
Mathlib.lean,Mathlib/Algebra/ContinuedFractions/Euler.lean |
2 |
15 |
['github-actions', 'mathlib-bors', 'wwylele'] |
alreadydone assignee:alreadydone |
5-924 5 days ago |
36-29059 36 days ago |
36-32580 36 days |
| 39256 |
Sfgangloff author:Sfgangloff |
feat(SymbolicDynamics): add monotonicity lemma for LanguageOn |
In Symbolic dynamics.
Proof that the language of a set of configurations is monotone with respect to inclusion of configuration sets:
X ⊆ Y → LanguageOn X U ⊆ LanguageOn Y U
The proof is a direct unfolding of definitions: a pattern in the language of X comes from restricting some configuration x ∈ X, and inclusion X ⊆ Y allows the same witness to be used for Y.
Related to issue #39252 |
t-dynamics
new-contributor
|
9/1 |
Mathlib/Dynamics/SymbolicDynamics/Basic.lean |
1 |
3 |
['github-actions'] |
ADedecker assignee:ADedecker |
5-923 5 days ago |
17-40173 17 days ago |
17-39942 17 days |
| 35287 |
arnoudvanderleer author:arnoudvanderleer |
feat(AlgebraicTopology/SimplicialSet): define isomorphisms in simplicial sets, and the coherent isomorphism simplicial set |
show that any edge in a simplicial set, that is the image of the forward edge of the coherent isomorphism under a simplicial set morphism, is an isomorphism.
---
[](https://gitpod.io/from-referrer/)
|
t-algebraic-topology
new-contributor
infinity-cosmos
|
362/3 |
Mathlib.lean,Mathlib/AlgebraicTopology/SimplicialSet/CoherentIso.lean,Mathlib/AlgebraicTopology/SimplicialSet/CompStruct.lean,Mathlib/AlgebraicTopology/SimplicialSet/NerveCodiscrete.lean,Mathlib/AlgebraicTopology/SimplicialSet/StdSimplex.lean,Mathlib/CategoryTheory/CodiscreteCategory.lean |
6 |
124 |
['arnoudvanderleer', 'dagurtomas', 'github-actions', 'joelriou', 'mathlib-merge-conflicts', 'robin-carlier'] |
robin-carlier assignee:robin-carlier |
4-56702 4 days ago |
4-56702 4 days ago |
35-57403 35 days |
| 38669 |
dannyply author:dannyply |
feat(Topology/Algebra/PontryaginDual): prove compact monoids have discrete duals |
Proves that the Pontryagin dual of a compact monoid is discrete. As a consequence, it also adds the corresponding finite-type instances for compact discrete monoids.
This upstreams a result first added downstream in [`YaelDillies/APAP`](https://github.com/YaelDillies/APAP), where this fact was needed to close a `sorry`. The proof separates the trivial character from all the others using the right half of the circle and adds a few reusable `Circle` helper lemmas near the existing related API.
The original APAP proof was AI-assisted and then reviewed/rewritten during downstream review. For this PR, I used Codex to help adapt the APAP proof to mathlib and to refactor the supporting lemmas.
---
[](https://gitpod.io/from-referrer/) |
t-topology
new-contributor
|
130/16 |
Mathlib/Analysis/SpecialFunctions/Complex/Circle.lean,Mathlib/Topology/Algebra/PontryaginDual.lean,Mathlib/Topology/MetricSpace/Pseudo/Defs.lean |
3 |
30 |
['dannyply', 'github-actions', 'j-loreaux', 'tb65536'] |
j-loreaux assignee:j-loreaux |
4-47057 4 days ago |
4-47057 4 days ago |
5-35505 5 days |
| 39820 |
samuelchassot author:samuelchassot |
Add proof of the existence of an Eulerian walk if all vertices have even degree or if exactly vertices have odd degree |
As per the TODO open in `Trails.lean`.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
671/3 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Eulerian.lean,Mathlib/Combinatorics/SimpleGraph/Trails.lean |
3 |
8 |
['SnirBroshi', 'copilot-pull-request-reviewer', 'github-actions'] |
nobody |
4-45899 4 days ago |
4-47130 4 days ago |
4-46899 4 days |
| 32583 |
MJ141592 author:MJ141592 |
refactor(SimpleGraph): change bridges not to require the edge to be present |
Remove the requirement for edges to exist in definition of isBridge, and then change the related lemmas to adjust for this, by renaming, fixing the statements and fixing the proofs, including in Acyclic.
Closes #31690.
---
- [x] depends on: #36802
- [x] depends on: #36804 |
t-combinatorics
new-contributor
|
95/93 |
Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/EdgeConnectivity.lean,Mathlib/Combinatorics/SimpleGraph/DeleteEdges.lean,Mathlib/Combinatorics/SimpleGraph/Hamiltonian.lean |
5 |
48 |
['MJ141592', 'Rida-Hamadani', 'SnirBroshi', 'YaelDillies', 'b-mehta', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts', 'mathlib4-merge-conflict-bot'] |
nobody |
4-43598 4 days ago |
4-43631 4 days ago |
53-85978 53 days |
| 39505 |
dannyhe652 author:dannyhe652 |
feat(SimpleGraph): add Vizing's theorem for edge coloring |
Hi! I'm a high school student interested in formulization of mathematics in Lean. Recently, I have worked on a project to formulize Vizing Theorem with Daniel Raggi from Cambridge University with AI assistance. In particular, we first drafted an outline for the proof, and built the proof using Claude Opus 4.5 and 4.6. The proof is optimized using Aristotle and finally reviewed by ourselves. We rewrote some parts of the code and some comments. The code now builds cleanly and we wish this code to be reviewed by Lean Community. I am aware that there are previous attempts, some being successful, on formulizing Vizing Theorem, including this one by Arohee https://github.com/aroheebhoja/vizing. However, I believe that no PR have been made. Our proof is not based on his proof, but it could be helpful for the community to review that project as well. I sincerely thank everyone who has time to verify and review our code. A summary of the project is as follows. Please contact me if there are any questions or problems.
## Summary
This PR completes the proof of **Vizing's theorem** for edge coloring in simple graphs, proving that the chromatic index of any graph is either Δ (the maximum degree) or Δ + 1.
## Changes
### New files
- **`Mathlib/Combinatorics/SimpleGraph/Coloring/EdgeColoring.lean`** — Core definitions
- `edgeColoring`: Type for line graph colorings
- `edgeColorable`: Graph is edge-colorable with n colors
- `chromaticIndex`: Chromatic index as ℕ
- **`Mathlib/Combinatorics/SimpleGraph/Coloring/KempeChain.lean`** — Kempe Chain
- Coloring observables: `incidentEdges`, `incidentColors`, `missingColors`
- Kempe subgraph structure with bounded degree
- `swapKempe`: Recolor edges in a connected component via color-swapping
- **`Mathlib/Combinatorics/SimpleGraph/Coloring/VizingFan.lean`** — Vizing Fan Rotation
- `IsFan`: Vizing fan structure with special color properties
- Fan maximality and dichotomy on terminal vertices
- `rotate_termA`: Extend coloring when a free color exists at both endpoints
- `vizingAdjacencyLemma`: Main adjacency lemma for both cases
- **`Mathlib/Combinatorics/SimpleGraph/Coloring/VizingTheorem.lean`** — Main theorems
- `edge_eq_of_color_eq`: Proper edge colorings assign different colors to distinct edges sharing a vertex
- `maxDegree_le_chromaticIndex`: χ'(G) ≥ Δ(G)
- `chromaticIndex_bot`: Empty graph has chromatic index 0
- `vizingUpperBound_aux`: Inductive proof of upper bound on number of edge
- `vizingTheorem`: χ'(G) ∈ {Δ(G), Δ(G) + 1}
### Modified files
- `Mathlib.lean` — Added imports for the four new coloring modules
## Technical Approach
**Lower bound** (χ'(G) ≥ Δ):
- Edges incident to a max-degree vertex form a clique in the line graph
- Clique number lower-bounds chromatic number
**Upper bound** (χ'(G) ≤ Δ + 1):
- Induction on the number of edges
- Base case: empty graph colored with 0 colors
- Inductive step:
- If a free color exists at both endpoints of an edge, then extend directly
- Otherwise:
- Build a maximal fan from one endpoint
- Apply dichotomy: either extend via Term-A (free color at both endpoints) or Term-B (Kempe swap)
- Term-B uses a three-vertex connectivity argument to derive a contradiction, forcing the fan to extend
## Key Lemmas
- `incidentEdges`, `incidentColors`, `missingColors`: Coloring observables at vertices
- `kempeSubgraph`: Restricted subgraph of edges with two specific colors
- `swapKempe`: Recolor via Kempe chain swapping
- `IsFan.singleton`: Trivial fan always valid
- `IsFan.length_le_card`: Fan length is bounded by vertex count
- `IsFan.dichotomy`: Maximal fan satisfies Term-A or Term-B
- `IsFan.rotate_termA`: Term-A case extends the coloring inductively
- `vizingAdjacencyLemma`: Handles both cases for extending one edge
- `vizingUpperBound_aux`: Framework for full inductive proof
- `edge_eq_of_color_eq`: Distinctness of edges with same color
## Testing
All four modules compile with no `sorry` nor errors or warnings.
## References
* V. G. Vizing, *On an estimate of the chromatic class of a p-graph*,
Diskret. Analiz. 3 (1964), 25–30.
## Co-authors
Co-authored-by: Daniel Raggi
Co-authored-by: Aristotle (Harmonic)
Co-authored-by: Claude Opus 4.5 & 4.6
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
LLM-generated
|
1915/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/EdgeColoring.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/KempeChain.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/VizingFan.lean,Mathlib/Combinatorics/SimpleGraph/Coloring/VizingTheorem.lean |
5 |
3 |
['github-actions'] |
nobody |
4-5044 4 days ago |
12-6805 12 days ago |
12-7953 12 days |
| 39282 |
Sfgangloff author:Sfgangloff |
feat(SymbolicDynamics): add union morphism lemma for LanguageOn |
In symbolic dynamics.
This PR proves that taking the language over a finite shape commutes with unions of configuration sets:
$LanguageOn (X \cup Y) U = LanguageOn X U \cup LanguageOn Y U$
The proof is a direct unfolding of definitions: a pattern in the language of $X \cup Y$ comes from restricting a configuration $x ∈ X \cup Y$, and splitting on whether $x \in X$ or $x \in Y$ yields the corresponding inclusion in either $LanguageOn X U$ or $LanguageOn Y U$. The converse direction rebuilds a witness in $X \cup Y$ from either side of the union.
Related to issue #39252 |
t-dynamics
new-contributor
|
15/1 |
Mathlib/Dynamics/SymbolicDynamics/Basic.lean |
1 |
2 |
['github-actions'] |
sgouezel assignee:sgouezel |
4-1212 4 days ago |
16-65228 16 days ago |
16-64997 16 days |
| 39722 |
kg583 author:kg583 |
feat(Combinatorics): Link `Nat.Partition` to `YoungDiagram` |
---
AI disclosure: Claude was used to source some proof sketches.
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
large-import
|
120/4 |
Mathlib.lean,Mathlib/Combinatorics/Enumerative/Partition/Basic.lean,Mathlib/Combinatorics/Enumerative/Partition/Conjugate.lean,Mathlib/Combinatorics/Young/YoungDiagram.lean |
4 |
36 |
['NoahW314', 'github-actions', 'kg583', 'wwylele'] |
nobody |
3-80925 3 days ago |
6-21734 6 days ago |
7-19078 7 days |
| 38275 |
TTony2019 author:TTony2019 |
feat: Add `AffineEquiv.image_intrinsicInterior` |
## Summary
This PR generalizes the existing lemma `AffineIsometry.image_intrinsicInterior` to the setting of affine equivalences, yielding the corresponding result `AffineEquiv.image_intrinsicInterior`.
Since affine equivalences are more general than affine isometries, the proof requires an additional finite-dimensionality assumption. The key extra input is that in finite-dimensional spaces, an affine equivalence induces a homeomorphism via `AffineEquiv.toHomeomorphOfFiniteDimensional`, so the assumptions are adjusted accordingly.
Apart from these extra assumptions, the argument is essentially the same as for `AffineIsometry.image_intrinsicInterior`.
## Collaboration
This PR was developed together with @imathwy.
|
t-analysis
new-contributor
|
283/41 |
Mathlib/Analysis/Convex/Intrinsic.lean,Mathlib/Analysis/Normed/Module/FiniteDimension.lean,Mathlib/LinearAlgebra/AffineSpace/Restrict.lean,Mathlib/Topology/Algebra/AffineSubspace.lean,Mathlib/Topology/Homeomorph/Defs.lean |
5 |
29 |
['TTony2019', 'github-actions', 'imathwy', 'j-loreaux', 'themathqueen'] |
j-loreaux assignee:j-loreaux |
3-62351 3 days ago |
3-62351 3 days ago |
20-52803 20 days |
| 39491 |
Yu-Misaka author:Yu-Misaka |
feat(Mathlib/LinearAlgebra/RootSystem/CartanMatrix): a Cartan matrix of a reduced crystallographic root system cannot have eigenvalue 4 |
This proves the TODO that a Cartan matrix of a reduced crystallographic root system cannot have eigenvalue 4.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-algebra
codex
LLM-generated
label:t-algebra$ |
125/8 |
Mathlib/Data/Matrix/Mul.lean,Mathlib/LinearAlgebra/RootSystem/CartanMatrix.lean,Mathlib/LinearAlgebra/RootSystem/GeckConstruction/Basis.lean,Mathlib/LinearAlgebra/RootSystem/GeckConstruction/Semisimple.lean |
4 |
6 |
['Yu-Misaka', 'copilot-pull-request-reviewer', 'github-actions', 'mathlib-bors', 'ocfnash'] |
ocfnash assignee:ocfnash |
3-59435 3 days ago |
3-59524 3 days ago |
3-59303 3 days |
| 39864 |
8e7 author:8e7 |
feat(Combinatorics/SimpleGraph/Acyclic): helly property on subtrees |
This PR adds several lemmas regarding connected subsets of vertices in trees (subtrees). The main result is the Helly property for subtrees: For a finite set of subtrees, if any pair of subtrees intersect, then there is a common vertex in all subtrees.
This lemma is part of an effort to formalize tree decompositions (see #38334), and will be used in a future PR to prove `G.cliqueNum - 1 <= G.treeWidth`.
AI Usage: The proofs were developed with the help of Claude Code. I vouch for all the code written and understand the content fully.
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
LLM-generated
|
114/0 |
Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Subgraph.lean |
2 |
2 |
['github-actions'] |
nobody |
3-37419 3 days ago |
3-58932 3 days ago |
3-58815 3 days |
| 39863 |
thomaskwaring author:thomaskwaring |
feat(Topology/Sets/Opens): Heyting-algebra operations on open sets |
Add expressions for the Heyting-algebra operations on the frame of opens subsets of a topological space.
---
[](https://gitpod.io/from-referrer/)
|
t-topology
new-contributor
|
22/0 |
Mathlib/Topology/Sets/Opens.lean |
1 |
9 |
['eric-wieser', 'github-actions', 'thomaskwaring'] |
nobody |
3-9474 3 days ago |
3-55091 3 days ago |
3-62411 3 days |
| 37062 |
tannerduve author:tannerduve |
feat(Computability): Turing join and semilattice structure on Turing degrees |
## Summary
- Add `Partrec.kronecker` (equality test) and `Partrec.join` (disjoint union by parity) in `Partrec.lean`
- Prove `Nat.RecursiveIn` is closed under computable conditionals (`cond_const`, `cond`)
- Show each component reduces to the join (`left_le_join`, `right_le_join`) and the join is the least upper bound (`join_le`)
- Establish `SemilatticeSup` instance on `TuringDegree` |
t-computability
new-contributor
large-import
|
311/15 |
Mathlib/Computability/Partrec.lean,Mathlib/Computability/RecursiveIn.lean,Mathlib/Computability/TuringDegree.lean |
3 |
7 |
['Komyyy', 'github-actions', 'mathlib-merge-conflicts', 'tannerduve'] |
Komyyy assignee:Komyyy |
3-2367 3 days ago |
46-37445 46 days ago |
47-13108 47 days |
| 38582 |
dennj author:dennj |
feat(LinearAlgebra/Matrix): add Hadamard matrices |
Introduce `Matrix.IsHadamard` over a general `Ring R`, with the basic theory:
- `IsHadamard` and `IsComplexHadamard` predicates (Definitions 2.3.1 and 2.7.1
of de Launey–Flannery, *Algebraic Design Theory*).
- `IsHadamard.det_sq`: the Hadamard determinant identity `(det A)² = n^n`.
- `IsHadamard.det_ne_zero`: over an integral domain of characteristic zero.
- `IsHadamard.transpose`: `Aᵀ` is Hadamard whenever `A` is (Theorem 2.3.6),
proved over `[CommRing R] [IsDomain R] [CharZero R]` via the adjugate.
- `IsHadamard.card_eq_sq_of_const_row_sum`: a Hadamard matrix with constant
row sum `s` has order `s²` (slightly stronger than Theorem 2.3.7: the
constant-column-sum hypothesis is implied by orthogonality).
- `IsHadamard.kronecker`: the Sylvester (Kronecker product) construction.
- `IsHadamard.four_dvd_card`: order of a Hadamard matrix of order > 2 is
divisible by 4.
`Matrix.mul_eq_smul_one_symm`: if `M * N = c • 1` and `det M ≠ 0` over an
integral domain, then `N * M = c • 1`. Used here for the transpose proof, but
generally useful, analogous to how `mul_eq_one_comm` works over stably finite
rings, but covers the integral-domain case (e.g. `ℤ`, `ℤ[X]`) where matrix
inverses don't exist.
## References
Adds the de Launey–Flannery bibliography entry, cited from the new file.
Human-made PR with LLM used for proof golfing and documentation |
t-algebra
new-contributor
label:t-algebra$ |
270/0 |
Mathlib.lean,Mathlib/Algebra/Group/Action/Defs.lean,Mathlib/Algebra/Group/Commute/Defs.lean,Mathlib/Algebra/Star/Unitary.lean,Mathlib/LinearAlgebra/Matrix/HadamardMatrix.lean,docs/references.bib |
6 |
56 |
['JJYYY-JJY', 'dennj', 'eric-wieser', 'github-actions', 'themathqueen', 'wwylele'] |
themathqueen assignee:themathqueen |
3-915 3 days ago |
17-12967 17 days ago |
32-31776 32 days |
| 39391 |
emlis42 author:emlis42 |
feat(MeasureTheory/Integral): add integral_congr_uIoo |
This PR adds some congruence lemmas for interval integrals under `NoAtoms μ` and golfs some lemmas.
| Lemma | Heartbeats | Proof Elaboration Time |
---- | ---- | ----
`LocallyIntegrable.ae_hasDerivAt_integral` | 7684 → 5235 (−2449, 31%) | 603ms → 445ms (−157ms, 26%)
`MonotoneOn.exists_tendsto_deriv_liminf_lintegral_enorm_le` | 31019 → 8388 (−22631, 73%) | 2475ms → 631ms (−1843ms, 74%)
`MonotoneOn.intervalIntegral_deriv_mem_uIcc` | 22680 → 5983 (−16697, 73%) | 1713ms → 537ms (−1175ms, 68%)
`AbsolutelyContinuousOnInterval.integral_deriv_mul_eq_sub` | 1475 → 845 (−630, 42%) | 92ms → 41ms (−50ms, 55%)
`fourierCoeff_liftIco_eq` | 1040 → 703 (−337, 32%) | 55ms → 41ms (−13ms, 24%)
`taylor_integral_remainder_aux` | 26585 → 18827 (−7758, 29%) | 2095ms → 1575ms (−520ms, 24%)
Profiled on top of commit `9e407aa1ef1be515a1bd0e1c1fc081d5b855f25e` using `set_option trace.profiler true in` and
```
set_option Elab.async false in
#count_heartbeats in
```
|
t-measure-probability
new-contributor
|
52/35 |
Mathlib/Analysis/Calculus/Taylor.lean,Mathlib/Analysis/Fourier/AddCircle.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/AbsolutelyContinuousFun.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/Basic.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/DerivIntegrable.lean,Mathlib/MeasureTheory/Integral/IntervalIntegral/LebesgueDifferentiationThm.lean |
6 |
3 |
['github-actions', 'mathlib-merge-conflicts'] |
kex-y assignee:kex-y |
3-911 3 days ago |
4-36547 4 days ago |
13-28739 13 days |
| 39369 |
pd4st8hb95-hub author:pd4st8hb95-hub |
feat: add basic fuzzy set definitions |
This PR adds a minimal `FuzzySet` API in `Mathlib/Order/FuzzySet`.
A fuzzy set is represented as an abbreviation:
`FuzzySet α L := α → L`
The file provides basic definitions and lemmas:
- `degree`
- `support`
- `core`
- `weakCut`
- `strongCut`
- membership simp lemmas
- extensionality
- basic monotonicity lemmas for weak and strong cuts
This PR intentionally does not add complement, union/intersection-specific API, normal or convex fuzzy sets, fuzzy relations, or advanced fuzzy set theory.
Validation:
- `lake build Mathlib.Order.FuzzySet`
- `#lint only docBlame docBlameThm`
Feedback on whether `Mathlib/Order/FuzzySet.lean` is the right location for this minimal API would be appreciated.
---
[](https://gitpod.io/from-referrer/)
|
t-order
new-contributor
|
169/0 |
Mathlib.lean,Mathlib/Order/FuzzySet.lean |
2 |
6 |
['github-actions', 'grunweg', 'pd4st8hb95-hub', 'wwylele'] |
nobody |
2-45072 2 days ago |
13-42673 13 days ago |
13-42802 13 days |
| 37071 |
ericluap author:ericluap |
feat: Dedekind completion of rationals is isomorphic to EReal |
|
t-order
new-contributor
|
128/4 |
Mathlib.lean,Mathlib/Data/EReal/Basic.lean,Mathlib/Data/EReal/DedekindCut.lean,Mathlib/Order/Completion.lean |
4 |
59 |
['ericluap', 'github-actions', 'plp127', 'vihdzp', 'wwylele'] |
vihdzp assignee:vihdzp |
2-23215 2 days ago |
18-34373 18 days ago |
41-29330 41 days |
| 39865 |
eliasjudin author:eliasjudin |
feat(Algebra): add eval API parity lemmas |
Adds two eval API parity lemmas from #23044: `MvPolynomial.hom_eval₂`, parallel to `Polynomial.hom_eval₂`, and `Polynomial.eval₂RingHom_comp_C`, parallel to `MvPolynomial.eval₂Hom_comp_C`.
This addresses the eval portion of #23044; the degree-name discussion there is left for separate work.
|
t-algebra
new-contributor
label:t-algebra$ |
10/0 |
Mathlib/Algebra/MvPolynomial/Eval.lean,Mathlib/Algebra/Polynomial/Eval/Defs.lean |
2 |
2 |
['github-actions'] |
nobody |
2-18285 2 days ago |
3-61992 3 days ago |
3-61761 3 days |
| 39811 |
TheGoedeDoel author:TheGoedeDoel |
feat(CategoryTheory): functors of submonoids |
We add a definition of a functor of submonoids: For a functor `M : C ⥤ MonCat`, a submonoid functor consists of a submonoid of `M.obj U` for every `U`, compatible with the restriction maps `M.map i`. We provide the complete lattice structure on `SubmonoidFunctor M` and a map and comap operation.
In a follow-up PR, we will use this to define the localisation of a presheaf of modules along a submonoid functor of the sheaf of rings.
See also https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Subfunctors.20with.20algebraic.20structure/with/587726088 for a discussion of alternative designs.
---
[](https://gitpod.io/from-referrer/)
|
t-category-theory
new-contributor
maintainer-merge
|
183/2 |
Mathlib.lean,Mathlib/Algebra/Group/Submonoid/Operations.lean,Mathlib/CategoryTheory/Subfunctor/SubmonoidFunctor.lean |
3 |
110 |
['TheGoedeDoel', 'chrisflav', 'github-actions', 'joelriou', 'quantumsnow'] |
chrisflav assignee:chrisflav |
2-16014 2 days ago |
3-26689 3 days ago |
3-43438 3 days |
| 39495 |
hawkrobe author:hawkrobe |
feat(Data/Multiset/Antidiagonal): two structural lemmas |
Adds `map_swap_antidiagonal` and `antidiagonal_add`.
---
Fills out the API parallel to `Multiset.Nat.map_swap_antidiagonal` and `Finset.map_swap_antidiagonal`. (And adds `@[congr]` to `bind_congr`.)
Used downstream for shuffle-coproduct constructions.
(#7486, I found this old [Zulip thread](https://leanprover.zulipchat.com/#narrow/channel/144837-PR-reviews/topic/antidiagonals.20having.20multiplicity.20.237595/near/238573473))
I used Claude Code to audit and polish. |
t-data
new-contributor
|
20/0 |
Mathlib/Data/Multiset/Antidiagonal.lean,Mathlib/Data/Multiset/Bind.lean |
2 |
6 |
['github-actions', 'hawkrobe', 'j-loreaux'] |
nobody |
2-2090 2 days ago |
9-46527 9 days ago |
12-27288 12 days |
| 37714 |
mortarsanjaya author:mortarsanjaya |
feat(Algebra/Order/Floor/Defs): `Nat.cast` is strictly monotone in `FloorSemiring` and `FloorRing` |
As title says, and without the `IsOrderedRing` assumption.
Other than that, I removed the `IsOrderedRing` assumption from pretty much all the lemmas in `Algebra/Order/Floor/Defs` that could possibly have this assumption removed, and reduced some `IsStrictOrderedRing` assumptions to `IsOrderedRing` + `Nontrivial`.
Due to strict monotonicity, we can also provide `CharZero` instance on `FloorSemiring` and `FloorRing`. Thus we can remove the `NeZero` and `Nontrivial` instances on them.
The changes on `/Ring` and `/Semiring` are trivial changes due to some lemmas not requiring an `IsOrderedRing` instance anymore.
---
[](https://gitpod.io/from-referrer/)
|
t-algebra
new-contributor
label:t-algebra$ |
96/39 |
Mathlib/Algebra/ContinuedFractions/Computation/Approximations.lean,Mathlib/Algebra/ContinuedFractions/Computation/TerminatesIffRat.lean,Mathlib/Algebra/Order/Floor/Defs.lean,Mathlib/Algebra/Order/Floor/Ring.lean,Mathlib/Algebra/Order/Floor/Semiring.lean |
5 |
24 |
['dagurtomas', 'eric-wieser', 'github-actions', 'mathlib-bors', 'mortarsanjaya'] |
riccardobrasca assignee:riccardobrasca |
2-1394 2 days ago |
28-48314 28 days ago |
52-47573 52 days |
| 38049 |
WilliamCoram author:WilliamCoram |
feat: lemmas towards showing gaussNorm on MvPowerSeries is an absolute value |
We prove lemmas: ``gaussNorm_mul_le`` and ``gaussNorm_le_mul`` which will allow us to show it is an absolute value on Mv restricted power series.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
new-contributor
|
144/1 |
Mathlib/RingTheory/MvPowerSeries/GaussNorm.lean |
1 |
4 |
['WilliamCoram', 'github-actions'] |
riccardobrasca assignee:riccardobrasca |
2-1392 2 days ago |
45-31183 45 days ago |
45-30952 45 days |
| 39294 |
Sfgangloff author:Sfgangloff |
feat(SymbolicDynamics): prove LanguageOn monotonicity under intersection |
In symbolic dynamics.
This PR proves that taking the language over a finite shape is monotone with respect to intersections of configuration sets:
```math
\mathrm{LanguageOn}(X \cap Y)\, U
\subseteq
\mathrm{LanguageOn}\, X\, U \cap \mathrm{LanguageOn}\, Y\, U
```
The proof is a direct unfolding of definitions: a pattern in the language of `X ∩ Y` comes from restricting a configuration `x ∈ X ∩ Y`. Since such an `x` belongs simultaneously to `X` and `Y`, the same restriction witness gives membership both in `LanguageOn X U` and in `LanguageOn Y U`, yielding membership in their intersection.
Related to issue #39252 |
t-dynamics
new-contributor
|
9/1 |
Mathlib/Dynamics/SymbolicDynamics/Basic.lean |
1 |
2 |
['github-actions'] |
ADedecker assignee:ADedecker |
2-1386 2 days ago |
16-56432 16 days ago |
16-56201 16 days |
| 39903 |
akiezun author:akiezun |
feat(NumberTheory): add almost prime numbers |
Adds Nat.IsAlmostPrime k n for natural numbers with exactly k prime factors counted with multiplicity, plus
Nat.IsAtMostAlmostPrime and Nat.IsSemiprime. The definitions reuse the existing arithmetic function Ω, and the initial
API proves the basic zero/one cases, prime examples, and closure under multiplication.
---
[](https://gitpod.io/from-referrer/)
|
new-contributor
t-number-theory
|
87/0 |
Mathlib.lean,Mathlib/NumberTheory/AlmostPrime.lean |
2 |
5 |
['SnirBroshi', 'akiezun', 'github-actions', 'vihdzp'] |
loefflerd assignee:loefflerd |
2-1379 2 days ago |
3-3451 3 days ago |
3-3220 3 days |
| 37374 |
NoneMore author:NoneMore |
feat(Topology/DerivedSet): add relative derived set lemmas |
Add `relDerivedSet`, `relDerivedSet_subset`, and `IsClosed.relDerivedSet_eq`.
---
[](https://gitpod.io/from-referrer/)
|
t-topology
new-contributor
|
17/0 |
Mathlib/Topology/DerivedSet.lean |
1 |
7 |
['NoneMore', 'github-actions', 'plp127', 'vihdzp'] |
fpvandoorn assignee:fpvandoorn |
1-68500 1 day ago |
1-68568 1 day ago |
59-33042 59 days |
| 38596 |
JJYYY-JJY author:JJYYY-JJY |
Add basic row-equivalence and echelon-form API for matrices |
This PR adds the first foundational slice of `Mathlib.LinearAlgebra.Matrix.Echelon`, a theorem-oriented API for elementary row operations, row-equivalence, and echelon-form predicates for matrices.
The main additions are:
* elementary row-scaling matrices and their `GL` versions;
* `Matrix.RowEquivalent` for the left action of `GL m R` on rectangular matrices;
* row-zero, pivot, echelon, and reduced-echelon predicates;
* semantic representative predicates `Matrix.IsEchelonFormOf` and `Matrix.IsReducedEchelonFormOf`.
This intentionally stops before row-space characterizations, existence and uniqueness of reduced echelon representatives, and the noncomputable canonical representative `Matrix.rref`; those are planned for later PRs.
Co-authored-by: Joseph Qian
Co-authored-by: Veer Shukla
Co-authored-by: Dhruv Bhatia
Co-authored-by: Zheng Wu <1036819072@qq.com>
---
This update trims the original full row-reduction API in response to reviewer feedback that the PR was too large. It keeps only the foundation needed by later row-reduction and `rref` PRs. |
t-algebra
new-contributor
label:t-algebra$ |
312/6 |
Mathlib.lean,Mathlib/LinearAlgebra/Matrix/Echelon.lean,Mathlib/LinearAlgebra/Matrix/Transvection.lean |
3 |
10 |
['JJYYY-JJY', 'SnirBroshi', 'copilot-pull-request-reviewer', 'dagurtomas', 'github-actions', 'wwylele'] |
nobody |
1-67963 1 day ago |
16-7489 16 days ago |
23-69081 23 days |
| 39841 |
hawkrobe author:hawkrobe |
feat(RingTheory/HopfAlgebra): Construction on primitive elements |
Adds `HopfAlgebra.ofPrimitives` which builds a Hopf algebra structure on a bialgebra generated by primitive elements, given a candidate anti-algebra hom that sends each generator to its negation.
---
The commutative case with `.ofAlgHom` gets this for free via `ext` but the non-commutative case needs extra work.
* [ ] depends on: #39785 |
t-ring-theory
new-contributor
|
314/20 |
Mathlib.lean,Mathlib/RingTheory/Bialgebra/Primitive.lean,Mathlib/RingTheory/HopfAlgebra/Basic.lean,Mathlib/RingTheory/HopfAlgebra/Generators.lean,Mathlib/RingTheory/HopfAlgebra/Primitive.lean,Mathlib/RingTheory/HopfAlgebra/TensorProduct.lean |
6 |
2 |
['github-actions'] |
nobody |
1-65098 1 day ago |
2-27056 2 days ago |
4-24241 4 days |
| 38027 |
8e7 author:8e7 |
feat(Combinatorics/SimpleGraph/Star): define star graphs |
Add a new definition `starGraph` and several key lemmas. Star graphs are a trivial class of tree, often used in constructive proofs regarding trees. An example use case is shown in #38334.
---
All lemmas are hand written first, then golfed with the help of Claude Code.
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
87/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Star.lean |
2 |
41 |
['8e7', 'IvanRenison', 'JovanGerb', 'SnirBroshi', 'b-mehta', 'github-actions', 'vihdzp', 'vlad902'] |
nobody |
1-62114 1 day ago |
43-80517 43 days ago |
45-78551 45 days |
| 39707 |
sorrachai author:sorrachai |
chore(Data/Tree/Basic): Rename Tree to BinaryTree |
Rename `Tree` to `BinaryTree`.
This frees up the name `Tree` to cover n-ary trees in future.
We only deprecate the `def`s, and move the theorems without deprecation. |
new-contributor
t-data
|
157/62 |
Mathlib/Combinatorics/Enumerative/Catalan/Tree.lean,Mathlib/Combinatorics/Enumerative/DyckWord.lean,Mathlib/Data/Tree/Basic.lean,Mathlib/Data/Tree/Get.lean,Mathlib/Data/Tree/Traversable.lean,Mathlib/Tactic/CancelDenoms/Core.lean,docs/overview.yaml |
7 |
36 |
['b-mehta', 'eric-wieser', 'github-actions', 'sorrachai'] |
nobody |
1-47635 1 day ago |
5-38867 5 days ago |
5-52694 5 days |
| 39785 |
hawkrobe author:hawkrobe |
refactor(RingTheory/HopfAlgebra): `ofConvInverse` constructor |
The antipode of a Hopf algebra is [generally](https://arxiv.org/pdf/1409.8356) the two-sided inverse of the identity in the convolution algebra `End(A)`. When `A` is commutative, algebra homs are closed under convolution and this lifts to AlgHom equality. See [this comment](https://github.com/leanprover-community/mathlib4/pull/31898#issuecomment-3566663278) on #31898.
---
Sadly the AlgHom-equality formulation is unavailable in the noncommutative case.
|
t-ring-theory
new-contributor
maintainer-merge
|
41/20 |
Mathlib/RingTheory/HopfAlgebra/Basic.lean,Mathlib/RingTheory/HopfAlgebra/TensorProduct.lean |
2 |
27 |
['YaelDillies', 'eric-wieser', 'faenuccio', 'github-actions', 'hawkrobe', 'themathqueen'] |
nobody |
1-42348 1 day ago |
1-79304 1 day ago |
4-71972 4 days |
| 38848 |
jcreinhold author:jcreinhold |
feat(AlgebraicTopology/SimplicialSet): exists_isPushout_of_ne_top |
Every proper subcomplex of a simplicial set extends by attaching a single cell along its boundary, exhibited as a pushout of `∂Δ[n] ↪ Δ[n]`. This is the per-cell input for cell-by-cell filtrations of monomorphisms in `SSet`.
Adapted from @joelriou 's [proof](https://github.com/joelriou/topcat-model-category/blob/813338a8c88cfe0096deed7e3ba7daf92d4a1c71/TopCatModelCategory/SSet/Boundary.lean#L187). I also added the supporting lemma `Types.isPullback_of_eq_setPreimage` (set-preimage square is a pullback in `Type u`).
AI use: Claude helped locate `subtype_val_mono` and the `backward.isDefEq.respectTransparency` option.
|
t-algebraic-topology
new-contributor
|
120/3 |
Mathlib/AlgebraicTopology/SimplicialSet/Boundary.lean,Mathlib/CategoryTheory/Limits/Types/Pullbacks.lean |
2 |
26 |
['github-actions', 'jcreinhold', 'joelriou', 'mckoen'] |
joelriou assignee:joelriou |
1-32961 1 day ago |
20-22916 20 days ago |
26-77862 26 days |
| 39790 |
hawkrobe author:hawkrobe |
feat(RingTheory): quotients of coalgebra/bialgebra/Hopf algebras |
---
Adds the quotient constructions suggested [here](https://github.com/leanprover-community/mathlib4/pull/39579#issuecomment-4529401418).
|
t-ring-theory
new-contributor
|
234/0 |
Mathlib.lean,Mathlib/RingTheory/Bialgebra/Quotient.lean,Mathlib/RingTheory/Coalgebra/Quotient.lean,Mathlib/RingTheory/HopfAlgebra/Quotient.lean |
4 |
9 |
['YaelDillies', 'github-actions', 'hawkrobe'] |
nobody |
1-28909 1 day ago |
1-79336 1 day ago |
3-84245 3 days |
| 33355 |
0xTerencePrime author:0xTerencePrime |
feat(Combinatorics/SimpleGraph/Connectivity): define vertex connectivity |
**AI Disclosure**: Developed with LLM assistance (Claude). All mathematical design decisions were made by the author.
---
This PR introduces the foundations of vertex connectivity for simple graphs, providing a counterpart to the edge connectivity theory in #32870.
### Main definitions
- `SimpleGraph.IsVertexReachable`: two vertices are `k`-vertex-reachable if they remain reachable after removing any set of strictly fewer than `k` vertices, using `G.induce sᶜ`.
- `SimpleGraph.IsVertexPreconnected`: a graph is `k`-vertex-preconnected if any two vertices are `k`-vertex-reachable.
- `SimpleGraph.IsVertexConnected`: a graph is `k`-vertex-connected if it is `k`-vertex-preconnected and has more than `k` vertices (`k + 1 ≤ ENat.card V`).
### Key lemmas
- `k = 0`: 0-connected ↔ nonempty; 0-preconnected always holds
- `k = 1`: 1-connected ↔ `Nontrivial V ∧ G.Preconnected`
- `anti` / `mono`: antitonic in `k`, monotonic in the graph |
new-contributor
t-combinatorics
LLM-generated
|
169/0 |
Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/VertexConnectivity.lean |
2 |
165 |
['0xTerencePrime', 'SnirBroshi', 'SproutSeeds', 'YaelDillies', 'github-actions', 'mathlib-merge-conflicts', 'vihdzp'] |
b-mehta assignee:b-mehta |
1-22318 1 day ago |
3-74386 3 days ago |
62-17027 62 days |
| 28613 |
espottesmith author:espottesmith |
feat(Combinatorics): define undirected hypergraphs |
This PR defines undirected hypergraphs:
```
@[ext]
structure Hypergraph (α : Type*) where
/-- The vertex set -/
vertexSet : Set α
/-- The hyperedge set -/
hyperedgeSet : Set (Set α)
/-- All hyperedges must be subsets of the vertex set -/
hyperedge_isSubset_vertexSet : ∀ ⦃e⦄, e ∈ hyperedgeSet → e ⊆ vertexSet
```
In addition to the main definition, some additional definitions and related lemmas are provided:
- vertex adjacency
- hyperedge adjacency
- vertex "stars"
- special cases (loops, empty hypergraphs, trivial hypergraphs, complete hypergraphs, simple hypergraphs, k-uniform hypergraphs, and d-regular hypergraphs)
- (some) hypergraph cardinality
- subhypergraphs, induced subhypergraphs, and partial hypergraphs
This implementation is certainly bare-bones. I'm submitting this PR at this point, rather than when my developments are more fleshed out, because there has been some interest in others contributing to hypergraph formalization in mathlib.
In the near future, goals include:
- defining incidence matrices (i.e., conversion from `Hypergraph α` to `Matrix α (Set α) β`
- coersion/generalization of graph as 2-uniform hypergraph
- conversion of a hypergraph into its associated clique graph/two-section graph
- constructing the dual of a hypergraph (note: on first blush, this appears somewhat challenging, given that we define hyperedges as `Set α` rather than some other type `β`)
- rank and co-rank
- walks, paths, cycles, etc. on hypergraphs
---
[](https://gitpod.io/from-referrer/)
|
t-combinatorics
new-contributor
|
286/0 |
Mathlib.lean,Mathlib/Combinatorics/Hypergraph/Basic.lean |
2 |
152 |
['SnirBroshi', 'b-mehta', 'espottesmith', 'github-actions', 'jt496', 'lauramonk', 'mathlib4-merge-conflict-bot', 'tb65536'] |
b-mehta assignee:b-mehta |
1-10355 1 day ago |
2-21955 2 days ago |
104-10373 104 days |
| 39629 |
hawkrobe author:hawkrobe |
feat(RingTheory/Coalgebra/Convolution): Algebra on convolution semiring |
This PR completes the algebraic structure on the convolution object.
---
I followed the pattern in [`Matrix/WithConv.lean`](https://github.com/leanprover-community/mathlib4/blob/5e932f97dd25535344f80f9dd8da3aab83df0fe6/Mathlib/LinearAlgebra/Matrix/WithConv.lean#L98) which splits out `IsScalarTower` and `SMulCommClass`. Used in pre-Lie / Oudom–Guin constructions. |
t-ring-theory
new-contributor
|
24/1 |
Mathlib/RingTheory/Coalgebra/Convolution.lean |
1 |
2 |
['github-actions'] |
nobody |
1-10195 1 day ago |
9-22137 9 days ago |
9-21906 9 days |
| 36103 |
SnkXyx author:SnkXyx |
feat(Algebra/MvPolynomial/CharacteristicSet): add Characteristic Set |
This PR adds some definitions and theorems of Characteristic Set Method (also known as Wu's Method).
Definitions:
* `MvPolynomial.mainDegree`
* `MvPolynomial.initialOf`
* `MvPolynomial.reducedTo`
* `TriangulatedSet`
* `MvPolynomial.pseudo`
* `MvPolynomial.setPseudo`
* `MvPolynomial.isRemainder`
* `MvPolynomial.isSetRemainder`
* `AscendingSetTheory`
* `TriangulatedSet.isAscendingSet`
* `HasBasicSet`
* `TriangulatedSet.isCharacteristicSet`
* `MvPolynomial.List.characteristicSet`
* `MvPolynomial.List.zeroDecomposition`
Main Theorems:
* `MvPolynomial.initialOf_mul_eq`: $init_i(p \cdot q) = init_i(p) \cdot init_i(q)$ if there is no zero divisors in the coefficient ring.
* `TriangulatedSet.instWellFoundedLT`: The set of Triangulated Sets is well-founded under the lexicographic ordering.
* `MvPolynomial.pseudo_remainder_isRemainder`: The remainder $r$ of $g$ by $f$ is reduced with respect to $f$ and satisfies $init(f)^s \cdot g = q \cdot f + r$ for some $s \in \mathbb{N}$ and $q \in R[X_{\sigma}]$.
* `MvPolynomial.setPseudo_remainder_isSetRemainder`: The remainder $r$ of $g$ by a set $S$ is reduced with respect to $S$ and satisfies $(\prod S_i^{e_i}) \cdot g = \sum q_i \cdot S_i + r$ for some sequences $\{e_i\}$ and $\{q_i\}$.
* `MvPolynomial.setPseudo_remainder_eq_zero_of_mem`: The remainder of $p$ by a set $S$ is $0$ if $p \in S$.
* `MvPolynomial.List.basicSet_append_lt_of_exists_reducedToSet`: Appending an element which is reduced w.r.t. the basic set of list strictly decreases the order.
* `MvPolynomial.List.characteristicSet_isCharacteristicSet`: The computed Characteristic Set $CS$ satisfies the key algebraic property (pseudo-remainder of input polynomials is 0) and the geometric property ( $Zero(PS) \subseteq Zero(CS)$ ).
* `MvPolynomial.List.vanishingSet_eq_zeroDecomposition_union`: The zero set of a polynomial system $PS$ can be decomposed into a finite union of "quasi-varieties" defined by triangular sets:
$Zero(PS) = \bigcup_{CS \in \mathcal{ZD}} Zero(CS / \text{InitialProd}(CS))$
The PR is upstreamized from [github.com/WuProver/lean_characteristic_set](https://github.com/WuProver/lean_characteristic_set)
---
[](https://gitpod.io/from-referrer/)
- [x] depends on: #36386
- [x] depends on: #37791
|
t-algebra
new-contributor
label:t-algebra$ |
3860/0 |
Mathlib.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/AscendingSet.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/CharacteristicSet.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/Initial.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/MainDegree.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/Order.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/PseudoDivision.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/Reduce.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/StandardAscendingSet.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/TriangularSet.lean,Mathlib/Algebra/MvPolynomial/CharacteristicSet/WeakAscendingSet.lean,docs/references.bib |
12 |
21 |
['Hagb', 'github-actions', 'mathlib-dependent-issues', 'mathlib-merge-conflicts'] |
dagurtomas assignee:dagurtomas |
1-964 1 day ago |
3-75600 3 days ago |
26-43090 26 days |
| 39347 |
Sfgangloff author:Sfgangloff |
feat(SymbolicDynamics): refactor of Pattern and shift-invariance of shape languages for subshifts |
## Summary
This PR refactors Pattern.mulShift in Mathlib/Dynamics/SymbolicDynamics/Basic.lean and uses the cleaner definition to prove shift-invariance of the language of a subshift on a finite shape.
## Changes
Pattern.mulShift now returns a Pattern instead of a configuration (more natural).
- Old type: Pattern.mulShift : Pattern A G → G → (G → A)
- New type: Pattern.mulShift : Pattern A G → G → Pattern A G
- The result carries its support (p.support.image (v * ·)) and the
default-outside-support proof, so callers don't have to re-derive them.
The [IsLeftCancelMul G] hypothesis is moved to the lemmas that actually use it.
- The definition Pattern.mulShift itself no longer needs left-cancellation (it only
chooses a preimage noncomputably).
- The hypothesis is now stated on mulShift_config_apply_mul_left_of_mem and
mulOccursInAt_eq_cylinder directly, instead of being a section-level variable.
Renames following the type change.
- mulShift_apply_mul_left_of_mem → mulShift_config_apply_mul_left_of_mem (because we
now write (p.mulShift v).config instead of p.mulShift v).
New @[simp] and @[ext] lemmas for Pattern.
- Pattern.ext: two patterns are equal iff their supports agree and their
configurations agree on the support.
- Pattern.mulShift_support: the support of p.mulShift v is p.support.image (v * ·).
- Pattern.fromConfig_support: the support of fromConfig x U is U.
- Pattern.fromConfig_config_of_mem: on its support, fromConfig x U agrees with x.
New lemma Pattern.fromConfig_mulShift.
For a left inverse g' * g = 1, shifting the pattern fromConfig x U by g equals
fromConfig (mulShift g' x) (U.image (g * ·)).
New theorem MulSubshift.languageOn_image_mulShift.
For a subshift Y and elements g, g' with g * g' = 1 and g' * g = 1:
(fun p => p.mulShift g) '' Y.languageOn U = Y.languageOn (U.image (g * ·))
i.e. the language on the translated shape is exactly the image of the language on U
under the pattern-shift map. This gives a bijection between Y.languageOn U and
Y.languageOn (U.image (g * ·)), with inverse p ↦ p.mulShift g'. Stated for
left-cancellative monoids with an invertible element.
Updated docstrings for Pattern.mulShift and the renamed lemma to reflect the
bundled-Pattern return type and clarify which results need [IsLeftCancelMul G]. |
t-dynamics
new-contributor
|
142/48 |
Mathlib/Dynamics/SymbolicDynamics/Basic.lean |
1 |
3 |
['github-actions'] |
sgouezel assignee:sgouezel |
1-953 1 day ago |
15-82645 15 days ago |
15-82414 15 days |
| 40005 |
tautschnig author:tautschnig |
feat(Data/ZMod/Basic): isUnit characterisation in prime power moduli |
Add two lemmas characterising units in ZMod (p^n) via divisibility of the canonical lift:
isUnit_iff_not_prime_dvd_val: for prime p and n > 0,
IsUnit x ↔ ¬ p ∣ x.val.
not_isUnit_iff_prime_dvd_val: for prime p and n > 0,
¬ IsUnit x ↔ p ∣ x.val.
These specialise the existing isUnit_iff_coprime to prime power moduli, where the coprimality condition reduces to a simple divisibility check on the unique prime factor.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
|
15/0 |
Mathlib/Data/ZMod/Basic.lean |
1 |
3 |
['copilot-pull-request-reviewer', 'github-actions'] |
nobody |
0-61490 17 hours ago |
0-63808 17 hours ago |
0-63577 17 hours |
| 40006 |
tautschnig author:tautschnig |
feat(Data/ZMod/Basic): idempotents in ZMod (p^d) are exactly {0, 1} |
Add sq_eq_self_iff_eq_zero_or_one: in ZMod (p^d) for prime p and d > 0, x^2 = x iff x = 0 or x = 1.
This generalises eq_zero_or_one_of_sq_eq_self (which requires CancelMonoidWithZero, i.e., no zero divisors) to the prime-power case. ZMod (p^d) has zero divisors for d >= 2, so the mul_left_injective₀ argument used by the existing lemma does not apply. The proof works by lifting to ℕ, using that if gcd(a, b) = 1 and p^d | a*b then p^d divides one of a or b (by Euclid's lemma), then noting that a = x.val and b = x.val - 1 are consecutive naturals and hence coprime.
---
[](https://gitpod.io/from-referrer/)
|
t-data
new-contributor
|
56/0 |
Mathlib/Data/ZMod/Basic.lean |
1 |
2 |
['github-actions'] |
nobody |
0-58887 16 hours ago |
0-58957 16 hours ago |
0-59421 16 hours |
| 35672 |
dennj author:dennj |
feat(RingTheory/Polynomial/Cyclotomic): vanishing sums and fiber equidistribution at primitive roots |
## Summary
Building on `sum_eq_zero_iff_forall_eq` from #34592, this PR adds:
- cyclotomic_dvd_of_aeval_eq_zero, exists_int_smul_cyclotomic_of_natDegree_le_totient — integer polynomials vanishing at a primitive n-th root are divisible by cyclotomic n ℤ, and (for degree ≤ φ(n)) integer multiples of it.
- sum_eq_zero_iff_forall_eq and its ℤ / ZMod p variants — vanishing iff all coefficients equal.
- sum_fiber_eq_sum_fiber_of_sum_weighted_pow_eq_zero, card_fiber_eq_card_div_of_sum_pow_eq_zero — fiber equidistribution.
- cyclotomic_prime_coeff — the formula (cyclotomic p R).coeff i = if i < p then 1 else 0, generalising existing coeff_zero/coeff_one lemmas.
-
References: [deLauneyFlannery2011, Lemma 2.8.5] (underlying ℚ/ℕ fact) and [armario2024, Lemma 7 and Theorem 3] (ℤ statement and the fiber-counting application).
Theorems imported from: https://github.com/Latinum-Agentic-Commerce/AlgebraicDesignTheory
Human made PR with LLM used for documentation and proof golfing |
t-ring-theory
new-contributor
LLM-generated
|
128/2 |
Mathlib/RingTheory/Polynomial/Cyclotomic/Basic.lean,Mathlib/RingTheory/Polynomial/Cyclotomic/Roots.lean,docs/references.bib |
3 |
7 |
['dennj', 'github-actions', 'grunweg', 'ocfnash', 'riccardobrasca'] |
riccardobrasca assignee:riccardobrasca |
0-58690 16 hours ago |
24-20142 24 days ago |
42-34021 42 days |
| 39954 |
jihuang2024 author:jihuang2024 |
feat(Analysis/Polynomial): define Hurwitz stability and prove small-degree characterizations |
Proofs were developed with assistance from Claude Code. I have reviewed and understand all the code and can justify the design decisions.
This PR introduces the predicate Polynomial.IsHurwitzStable for real polynomials and proves the Routh–Hurwitz stability criterion for degrees 1 and 2.
A polynomial p : ℝ[X] is Hurwitz stable if every root of its complexification has strictly negative real part. This notion arises in control theory and the study of linear ODEs, where it characterises asymptotic stability of a system.
New definitions
Polynomial.IsHurwitzStable: ∀ z : ℂ, (p.map (algebraMap ℝ ℂ)).IsRoot z → z.re < 0
New theorems
Polynomial.not_isHurwitzStable_zero: the zero polynomial is not Hurwitz stable
Polynomial.IsHurwitzStable.ne_zero: Hurwitz stable polynomials are nonzero
Polynomial.isHurwitzStable_X_add_C: X + C a is Hurwitz stable ↔ 0 < a
Polynomial.isHurwitzStable_quadratic: X ^ 2 + C b * X + C c is Hurwitz stable ↔ 0 < b ∧ 0 < c
Proof strategy for the quadratic
The quadratic case splits on whether a root z is real (z.im = 0) or complex (z.im ≠ 0, which forces 2 * z.re + b = 0). Existence of a root uses Complex.exists_root (Fundamental Theorem of Algebra). The necessary condition in the real-root case uses the Vieta complementary root -b - z.re.
Future work
The general Routh–Hurwitz theorem (for degree n, stated in terms of the Hurwitz matrix and its leading principal minors) requires infrastructure not yet in Mathlib — in particular a theory of the Cauchy index or the Bezoutian of two polynomials. This PR lays the definitional foundation for that work.
This corresponds to [1000.yaml](https://github.com/leanprover-community/mathlib4/blob/master/docs/1000.yaml#L2697) Q4455015 - Routh–Hurwitz theorem |
t-analysis
new-contributor
LLM-generated
|
131/0 |
Mathlib.lean,Mathlib/Analysis/Polynomial/RouthHurwitz.lean |
2 |
10 |
['SnirBroshi', 'github-actions', 'jihuang2024', 'wwylele'] |
nobody |
0-44104 12 hours ago |
0-45937 12 hours ago |
1-50733 1 day |
| 32692 |
WilliamCoram author:WilliamCoram |
feat: define multivariate restricted power series |
We define multivariate restricted power series over a normed ring R, and show the properties that they form a ring when R has the ultrametric property.
This work generalises my previous work in #26089 which will need to be refactored.
---
[](https://gitpod.io/from-referrer/)
|
t-ring-theory
t-number-theory
new-contributor
|
159/0 |
Mathlib.lean,Mathlib/Algebra/Order/Antidiag/Prod.lean,Mathlib/Algebra/Order/Antidiag/Tendsto.lean,Mathlib/RingTheory/MvPowerSeries/Restricted.lean |
4 |
51 |
['WilliamCoram', 'erdOne', 'github-actions', 'jcommelin', 'mathlib-merge-conflicts', 'mbkybky'] |
jcommelin assignee:jcommelin |
0-38977 10 hours ago |
10-37053 10 days ago |
53-12444 53 days |
| 40016 |
xhalo32 author:xhalo32 |
feat(InfiniteSum): add hasProd_ite_eq' and tprod_ite_eq' |
Adds `eq'` variants that mirror those in `Mathlib/Algebra/BigOperators/Group/Finset/Piecewise.lean` and `Mathlib/Algebra/BigOperators/Finsupp/Basic.lean`.
For proof of their usefulness, these summability lemmas about indicator functions are now straight-forward:
```lean
theorem hasSum_indicator_singleton_const [CommMonoid α] [TopologicalSpace α] [TopologicalSpace β] [AddCommMonoid β]
{x : α} {f : α → β} (L := unconditional α) [L.LeAtTop]
: HasSum (fun y => Set.indicator {y} f x) (f x) L
:= by
classical
exact hasSum_ite_eq' x (f x) L
theorem summable_indicator_singleton_const [CommMonoid α] [TopologicalSpace α] [TopologicalSpace β] [AddCommMonoid β]
{x : α} {f : α → β} (L := unconditional α) [L.LeAtTop]
: Summable (fun y => Set.indicator {y} f x) L
:= ⟨_, hasSum_indicator_singleton_const _⟩
```
We are also depending on these proofs in [Polya-lean](https://github.com/alma-n/polya-lean).
Update: changed `convert` to `convert!`.
---
[](https://gitpod.io/from-referrer/)
|
t-topology
new-contributor
|
14/0 |
Mathlib/Topology/Algebra/InfiniteSum/Basic.lean |
1 |
3 |
['github-actions', 'xhalo32'] |
nobody |
0-31103 8 hours ago |
0-34387 9 hours ago |
0-38586 10 hours |
| 39996 |
RuthP628 author:RuthP628 |
feat(ModelTheory/Semantics): add simp theorems similar to Sentence.realize_not |
Add simp theorems Sentence.realize_bot, Sentence.realize_top, Sentence.realize_inf, Sentence.realize_sup, Sentence.realize_imp and Sentence.realize_iff in the style of Sentence.realize_not as consequences of the corresponding theorems for formulas. |
t-logic
new-contributor
|
31/1 |
Mathlib/ModelTheory/Semantics.lean |
1 |
10 |
['RuthP628', 'b-mehta', 'github-actions', 'plp127'] |
nobody |
0-17558 4 hours ago |
0-44564 12 hours ago |
0-51572 14 hours |
| 40033 |
JJYYY-JJY author:JJYYY-JJY |
chore: remove flexible linter suppressions |
This PR removes two local `linter.flexible` suppressions by replacing compact `simp; infer_instance` with explicit proofs.
Changed files:
- `Mathlib/Dynamics/TopologicalEntropy/DynamicalEntourage.lean`
- `Mathlib/Topology/UniformSpace/Ultra/Constructions.lean`
Tested with:
`lake build`
---
[](https://gitpod.io/from-referrer/)
|
new-contributor |
20/8 |
Mathlib/Dynamics/TopologicalEntropy/DynamicalEntourage.lean,Mathlib/Topology/UniformSpace/Ultra/Constructions.lean |
2 |
2 |
['github-actions'] |
nobody |
0-11058 3 hours ago |
0-11135 3 hours ago |
0-10904 3 hours |
| 38223 |
Deicyde author:Deicyde |
feat(Geometry/Manifold): add `MfldCat`, the category of `C^n` manifolds |
We define `MfldCat 𝕜 n`: the category of `C^n` manifolds over a field `𝕜`, following the pattern of `TopCat` in
`Mathlib.Topology.Category.TopCat.Basic`. We also implement `HasForget₂ (MfldCat 𝕜 n) TopCat`—the forgetful functor into the category of topological spaces. For more discussion see the Zulip thread: [#PR reviews > #38223 The Category of C^n Manifolds](https://leanprover.zulipchat.com/#narrow/channel/144837-PR-reviews/topic/.2338223.20The.20Category.20of.20C.5En.20Manifolds/with/587038032)
Also added: `ContMDiffMap.id_apply`, `.coe_id` and `.coe_comp` which are comparable to `ContinuousMap` API.
### Future work
- ✅ Define a Monoidal structure via product manifolds, analogous to `Manifold.Topology.Category.TopCat.Monoidal` #38560
- ✅ Define the tangent functor: `M ↦ TM`, `F ↦ F.tangentMap` from `MfldCat (n+1) 𝕜` to `MfldCat n 𝕜` #38270
- Functor `FGModuleCat 𝕜 ⥤ MfldCat 𝕜 n` sending a finite-dimensional `𝕜`-vector space to the manifold modeled on itself. Left as `TODO`.
- Define `FGModuleCat 𝕜` as an enriched category over `MfldCat n 𝕜`. Then _smooth functors_ can be realized as endofunctors on the enriched category. This is the main motivation for this construction.
---
[](https://gitpod.io/from-referrer/)
|
t-differential-geometry
new-contributor
t-category-theory
|
224/0 |
Mathlib.lean,Mathlib/Geometry/Manifold/Category/MfldCat/Basic.lean,Mathlib/Geometry/Manifold/ContMDiffMap.lean |
3 |
57 |
['Deicyde', 'chrisflav', 'dagurtomas', 'github-actions', 'idontgetoutmuch', 'peabrainiac'] |
nobody |
0-2540 42 minutes ago |
21-20720 21 days ago |
34-70605 34 days |
| 39868 |
JuanCoRo author:JuanCoRo |
feat(Algebra/Polynomial): linearity of `divByMonic` and adjacent results |
---
This PR adds the `R`-linearity of the monic polynomial division map `_ /ₘ q`. It also adds adjacent results that stem from this work.
#### Refactors:
- Reuses the proofs from `add_modByMonic` and `smul_modByMonic` to generalize these results to `add_div_modByMonic` and `smul_div_modByMonic` respectively.
- Replaces the proofs of `add_modByMonic` and `smul_modByMonic` as specializations of the more general theorems `add_div_modByMonic` and `smul_div_modByMonic` respectively.
#### Additions:
- Adds the necessary results for `_ /ₘ q` linearity:
- `add_divByMonic : (p₁ + p₂) /ₘ q = p₁ /ₘ q + p₂ /ₘ q`
- `smul_divByMonic : c • p /ₘ q = c • (p /ₘ q)`
- Adds `_ /ₘ q` as an `R`-linear map:
- `divByMonicHom`: definition of `_ /ₘ q` as a linear map
- `mem_ker_divByMonic`: kernel characterization for `_ /ₘ q`.
- In `Div.lean` adds dual results for `/ₘ` that were already present for `%ₘ`
- `neg_divByMonic : (-p) /ₘ q = -(p /ₘ q)`
- `sub_divByMonic : (p₁ - p₂) /ₘ q = p₁ /ₘ q - p₂ /ₘ q`
- `mul_divByMonic_assoc (hd : q ∣ p₂) : (p₁ * p₂) /ₘ q = p₁ * (p₂ /ₘ q)`
While `mul_divByMonic_assoc` is not exactly the dual of `mul_modByMonic`, I thought it wouldn't hurt to add it.
[](https://gitpod.io/from-referrer/) |
new-contributor
t-algebra
label:t-algebra$ |
54/17 |
Mathlib/Algebra/Polynomial/Div.lean,Mathlib/Algebra/Polynomial/RingDivision.lean |
2 |
4 |
['github-actions', 'wwylele'] |
nobody |
0-2159 35 minutes ago |
0-52203 14 hours ago |
0-52051 14 hours |
| 38527 |
archiebrowne author:archiebrowne |
feat(Analysis/Calculus): continuously differentiable actions |
define the class `ContDiffSMul 𝕜 M X n` which asserts that the map `(c, x) ↦ c • x` is `n` times continuously differentiable on `M × X`.
Many of the results are the C^n analogues of those in the module Mathlib.Topology.Algebra.MulAction.
|
t-differential-geometry
new-contributor
|
317/24 |
Mathlib.lean,Mathlib/Analysis/Calculus/BumpFunction/Basic.lean,Mathlib/Analysis/Calculus/ContDiff/Operations.lean,Mathlib/Analysis/Calculus/IteratedDeriv/Lemmas.lean,Mathlib/Analysis/ContDiffMulAction.lean,Mathlib/Analysis/InnerProductSpace/Calculus.lean |
6 |
11 |
['archiebrowne', 'github-actions', 'grunweg', 'peabrainiac'] |
ocfnash assignee:ocfnash |
0-1201 20 minutes ago |
22-18401 22 days ago |
30-4079 30 days |
| 38551 |
TTony2019 author:TTony2019 |
feat(Analysis/Convex/Intrinsic): add `affineSpan_prod_eq` and `intrinsicInterior_prod_eq` |
### Summary
We prove that the affine span of a product set equals the product of the affine spans, and that the intrinsic interior of a product set equals the product of the intrinsic interiors.
- `affineSpan_prod_eq`: for `s : Set P₁` and `t : Set P₂`, `affineSpan k (s ×ˢ t) = (affineSpan k s) ×ˢ (affineSpan k t)` as sets.
- `intrinsicInterior_prod_eq`: for `s : Set P` and `t : Set Q`, `intrinsicInterior 𝕜 (s ×ˢ t) = intrinsicInterior 𝕜 s ×ˢ intrinsicInterior 𝕜 t`.
These two theorems are added to `Mathlib/LinearAlgebra/AffineSpace/AffineSubspace/Basic.lean` and `Mathlib/Analysis/Convex/Intrinsic.lean`.
### Collaboration
Co-authored-by: @imathwy |
new-contributor
t-analysis
|
144/0 |
Mathlib/Algebra/AddTorsor/Basic.lean,Mathlib/Algebra/Group/Pointwise/Set/Basic.lean,Mathlib/Analysis/Convex/Intrinsic.lean,Mathlib/LinearAlgebra/AffineSpace/AffineSubspace/Basic.lean,Mathlib/LinearAlgebra/Prod.lean |
5 |
24 |
['TTony2019', 'github-actions', 'wwylele'] |
themathqueen assignee:themathqueen |
0-1200 20 minutes ago |
30-83302 30 days ago |
33-26944 33 days |
| 38895 |
emlis42 author:emlis42 |
chore(Algebra/ContinuedFractions): golf |
This PR simplifies some proofs in `Algebra/ContinuedFractions` |
t-algebra
new-contributor
label:t-algebra$ |
39/63 |
Mathlib/Algebra/ContinuedFractions/Computation/ApproximationCorollaries.lean,Mathlib/Algebra/ContinuedFractions/Computation/Approximations.lean,Mathlib/Algebra/ContinuedFractions/Computation/CorrectnessTerminating.lean,Mathlib/Algebra/ContinuedFractions/Computation/TerminatesIffRat.lean,Mathlib/Algebra/ContinuedFractions/Computation/Translations.lean,Mathlib/Algebra/ContinuedFractions/ContinuantsRecurrence.lean,Mathlib/Algebra/ContinuedFractions/ConvergentsEquiv.lean |
7 |
2 |
['github-actions'] |
joelriou assignee:joelriou |
0-1197 19 minutes ago |
25-5560 25 days ago |
25-80032 25 days |
| 40026 |
thefundamentaltheor3m author:thefundamentaltheor3m |
feat(ArithmeticFunction/Defs): A power of a multiplicative arithmetic function is multiplicative |
---
[](https://gitpod.io/from-referrer/)
|
t-number-theory
new-contributor
|
9/0 |
Mathlib/NumberTheory/ArithmeticFunction/Defs.lean |
1 |
2 |
['github-actions', 'wwylele'] |
MichaelStollBayreuth assignee:MichaelStollBayreuth |
0-1185 19 minutes ago |
0-27648 7 hours ago |
0-27417 7 hours |
| 38534 |
AlexeyMilovanov author:AlexeyMilovanov |
refactor(Computability): bundle PFun into a structure with FunLike instance |
This PR refactors `PFun` from `def PFun α β := α → Part β` to a structure with a `FunLike` instance.
[Discussion](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Fix.20for.20fun_prop.20on.20PFun.20.28context.3A.20Computability.20Theory.29)
### Main changes
* `PFun` is now a structure with a single field `toFun : α → Part β`.
* Added the `FunLike (α →. β) α (Part β)` instance and `initialize_simps_projections`.
* Added the basic projection/application simp lemmas needed for the structure wrapper.
* Definitions which used to return raw lambdas as partial functions now explicitly use `PFun.mk` or `PFun.lift`.
* Equality proofs for partial functions now use `PFun.ext` / `DFunLike.ext` where `funext` no longer applies directly.
### Downstream impact
The refactor mainly impacts Computability Theory and Category Theory (`Category/PartialFun.lean`). Since `PFun` is no longer definitionally equal to `α → Part β`, tactics such as `rfl`, `simp`, and `funext` can no longer always see through the old raw-function representation.
As a result, several proofs (e.g. `fix_aux`, `ppred`, `mem_eval`, and `unitIso`) grew in size, requiring explicit `ext` + `simp` breakdowns. I tried to keep these proof changes minimal; further golfing suggestions are very welcome. It seems that fully recovering the old brevity in some places may require additional `PFun`-specific API/congruence support, which I avoided adding in this PR to keep the diff minimal.
### Affected files
* **Core:** `Mathlib/Data/PFun.lean`
* **Computability:** `Partrec`, `PartrecBasis`, `PartrecCode`, `RE`, `RecursiveIn`, `Ackermann`, `Halting`, `StateTransition`, `TuringDegree`, `TuringMachine/Config`
* **Category Theory:** `Category/PartialFun.lean`
* **Other:** `Data/Finset/PImage.lean`, `NumberTheory/Dioph.lean`
This also removes the previous `set_option linter.flexible false` workaround and the local transparency workaround in `TuringMachine/Config.lean`, as well as the local transparency workarounds in `Category/PartialFun.lean`.
### Note on LLM usage
The core `PFun` change caused numerous downstream errors. I initially used an LLM to help draft fixes for these files. Afterwards, I spent a significant amount of time manually correcting and modifying all of the generated changes.
|
new-contributor
t-computability
|
821/599 |
Mathlib/CategoryTheory/Category/PartialFun.lean,Mathlib/Computability/Ackermann.lean,Mathlib/Computability/Halting.lean,Mathlib/Computability/Partrec.lean,Mathlib/Computability/PartrecBasis.lean,Mathlib/Computability/PartrecCode.lean,Mathlib/Computability/RE.lean,Mathlib/Computability/RecursiveIn.lean,Mathlib/Computability/StateTransition.lean,Mathlib/Computability/TuringDegree.lean,Mathlib/Computability/TuringMachine/Config.lean,Mathlib/Data/Finset/PImage.lean,Mathlib/Data/PFun.lean,Mathlib/NumberTheory/Dioph.lean |
14 |
9 |
['AlexeyMilovanov', 'dagurtomas', 'github-actions', 'j-loreaux', 'mathlib-bors', 'mathlib-merge-conflicts'] |
nobody |
0-581 9 minutes ago |
4-15207 4 days ago |
12-42719 12 days |