The mathlib review queue

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This dashboard was last updated on: January 08, 2026 at 13:13 UTC

Review queue

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
27100 staroperator
author:staroperator
feat(ModelTheory): Presburger definability and semilinear sets This PR formalizes the classical result that Presburger definable sets are the same as semilinear sets. As an application of this result, we show that the graph of multiplication is not Presburger definable. --- - [x] depends on: #26896 - [x] depends on: #27081 - [x] depends on: #27087 - [x] depends on: #27414 - [x] depends on: #32123 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic 298/0 Mathlib.lean,Mathlib/ModelTheory/Arithmetic/Presburger/Definability.lean,Mathlib/ModelTheory/Arithmetic/Presburger/Semilinear/Defs.lean,docs/references.bib 4 6 ['github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] fpvandoorn
assignee:fpvandoorn
37-43913
1 month ago
40-79537
1 month ago
42-79960
42 days
32124 SnirBroshi
author:SnirBroshi
feat(SimpleGraph/Walks/Operations): expand basic drop/take/reverse API --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 44/0 Mathlib/Combinatorics/SimpleGraph/Walks/Operations.lean 1 1 ['github-actions'] awainverse
assignee:awainverse
37-43903
1 month ago
43-36213
1 month ago
43-36253
43 days
29942 smmercuri
author:smmercuri
feat(InfinitePlace/Completion): embeddings of `w.Completion` factor through embeddings of `v.Completion` when `w` extends `v` If `w : v.Extension L` is an extension of `v : InfinitePlace K` to `L`, then `extensionEmbedding w : L →+* ℂ` factors through `extensionEmbedding v : K →+* ℂ`. --- - [x] depends on: #27978 - [x] depends on: #29969 - [x] depends on: #29944 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) FLT 89/14 Mathlib/Analysis/Normed/Field/WithAbs.lean,Mathlib/NumberTheory/NumberField/InfinitePlace/Completion.lean,Mathlib/NumberTheory/NumberField/InfinitePlace/Embeddings.lean,Mathlib/NumberTheory/NumberField/InfinitePlace/Ramification.lean,Mathlib/Topology/MetricSpace/Completion.lean 5 5 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] joelriou
assignee:joelriou
36-67696
1 month ago
40-67666
1 month ago
40-68758
40 days
29393 staroperator
author:staroperator
feat(SetTheory/ZFC): `card (V_ o) = preBeth o` --- - [x] depends on: #26544 - [x] depends on: #29351 - [x] depends on: #29365 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-set-theory large-import 37/4 Mathlib/SetTheory/ZFC/Ordinal.lean,Mathlib/SetTheory/ZFC/VonNeumann.lean 2 5 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'staroperator', 'vihdzp'] alreadydone
assignee:alreadydone
36-43899
1 month ago
40-33978
1 month ago
40-36599
40 days
32238 YaelDillies
author:YaelDillies
feat(Combinatorics/SimpleGraph): distributivity of box product over sum From ProofBench --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics large-import 21/2 Mathlib/Combinatorics/SimpleGraph/Prod.lean 1 1 ['github-actions'] kmill
assignee:kmill
36-43889
1 month ago
39-81236
1 month ago
39-81267
39 days
32367 BoltonBailey
author:BoltonBailey
feat(Computability): add finEncodings for List Bool and pairs of types This PR contains `finEncoding`s relevant to developing complexity theory in downstream libraries. It is adapted from [this](https://leanprover.zulipchat.com/#narrow/channel/116395-maths/topic/Formalise.20the.20proposition.20P.20.E2.89.A0NP/near/451765788)[#maths > Formalise the proposition P ≠NP @ 💬](https://leanprover.zulipchat.com/#narrow/channel/116395-maths/topic/Formalise.20the.20proposition.20P.20.E2.89.A0NP/near/451765788) comment. Co-authored-by: Daniel Weber --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-computability 58/3 Mathlib/Computability/Encoding.lean,Mathlib/Data/List/Basic.lean,Mathlib/Data/Sum/Basic.lean 3 2 ['MichaelStollBayreuth', 'github-actions'] nobody
31-68064
1 month ago
31-68183
1 month ago
36-62612
36 days
31610 rudynicolop
author:rudynicolop
feat(Computability/NFA): Kleene star closure for Regular Languages via NFA This PR constructs a Kleene star closure for non-epsilon NFAs, and proves that regular languages are closed under Kleene star. The NFA construction is `NFA.kstar`. The main theorems are: - `NFA.accepts_kstar`: demonstrates that `M.kstar` accepts the Kleene star closure of the language of `M`. - `IsRegular.kstar`: demonstrates that regular languages are closed under Kleene star. There is an onging zulip discussion about regular languages in Mathlib: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Regular.20languages.3A.20the.20review.20queue/with/553759136 This discussion is also tracked at #24205. Furthermore, the construction and proofs in this PR are heavily inspired by @TpmKranz from his #15651. #15651 supersedes this PR, so if it is accepted then this PR is not needed. --- - [x] depends on: #31038 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-computability 405/7 Mathlib/Computability/NFA.lean 1 5 ['ctchou', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] nobody
31-52122
1 month ago
37-55324
1 month ago
37-58274
37 days
32374 adamtopaz
author:adamtopaz
feat(Tactic/WildcardUniverse): Foo.{*, _, v*, max u v} This PR creates an elaborator for syntax of the form `Foo.{*, _, v*, max u v}`. A `*` indicates that a new universe parameter should be created, `_` and `max u v` elaborate using the existing level elaboration (so `_` elaborates to a level mvar). The syntax `v*` creates a level parameter of the form `v_n` for some value of `n`. The newly created level parameters are ordered in a particular way to match the order in which they appear in the syntax. For example, in `Foo.{*, _, v*, max u v}`, the level parameter associated with `*` will come before the other universes, including the parameter created by `v*`, and the parameters `u` and `v`. Similarly the parameter associated with `v*` will come *after* the one for `*`, and before both `u` and `v`. Note: Unlike `Category* C`, where we understand exactly how the universes involved in `C` (both in the term and its type) relate to the level parameter of the morphisms, we can't expect such precise control in general. For example, when `C.{u} : Type 0`, `Category* C` places the morphism level `v_1` before `u`, but `Category.{*} C` places it after `u`. In other words, `Foo.{...}` only reorders the level parameters based on the parameters that appear in the (elaborated) `...`, without any regard to the universes that appear in the *arguments* to `Foo.{...}`. Co-authored-by: Claude --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta 703/0 Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/WildcardLevel.lean,MathlibTest/WildcardLevel.lean 4 25 ['JovanGerb', 'adamtopaz', 'github-actions'] dwrensha
assignee:dwrensha
31-43905
1 month ago
34-50236
1 month ago
35-54833
35 days
32273 jsm28
author:jsm28
feat(Analysis/Convex/Side): affine combinations on same / opposite side of face of a simplex as a vertex Build on #31205 by providing lemmas about when an affine combination of the vertices of a simplex is on the same / opposite side of a face (opposite a vertex) of the simplex as that vertex (a specific case of the lemmas from #31205 which involve two arbitrary affine combinations). --- - [ ] depends on: #31205 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis t-convex-geometry 62/0 Mathlib/Analysis/Convex/Side.lean 1 3 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] nobody
31-6052
1 month ago
31-6081
1 month ago
31-13657
31 days
32455 vihdzp
author:vihdzp
feat: order topologies of successor orders --- Co-authored by @j-loreaux [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology t-order 124/43 Mathlib.lean,Mathlib/Order/Cover.lean,Mathlib/SetTheory/Ordinal/Topology.lean,Mathlib/Topology/Order/SuccPred.lean 4 1 ['github-actions'] pechersky
assignee:pechersky
30-43904
30 days ago
34-31219
1 month ago
34-31206
34 days
31059 gasparattila
author:gasparattila
feat(Topology/Sets): define the Vietoris topology on `(Nonempty)Compacts` This PR defines the Vietoris topology on `Compacts` and `NonemptyCompacts`, and proves that it is induced by the Hausdorff uniformity. --- - [x] depends on: #31031 - [x] depends on: #31058 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology 257/29 Mathlib.lean,Mathlib/Data/Rel.lean,Mathlib/Topology/MetricSpace/Closeds.lean,Mathlib/Topology/Sets/Compacts.lean,Mathlib/Topology/Sets/VietorisTopology.lean,Mathlib/Topology/UniformSpace/Closeds.lean,docs/references.bib 7 6 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'robin-carlier'] ADedecker
assignee:ADedecker
27-61261
27 days ago
27-75447
27 days ago
48-35598
48 days
30112 gaetanserre
author:gaetanserre
feat(Probability.Kernel): add representation of kernel as a map of a uniform measure Add results about isolation of kernels randomness. In particular, it shows that one can write a Markov kernel as the map by a deterministic of a uniform measure on `[0, 1]`. It corresponds to Lemma 4.22 in "[Foundations of Modern Probability](https://link.springer.com/book/10.1007/978-3-030-61871-1)" by Olav Kallenberg, 2021. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability 149/0 Mathlib.lean,Mathlib/Probability/Kernel/Representation.lean 2 4 ['RemyDegenne', 'gaetanserre', 'github-actions', 'mathlib4-merge-conflict-bot'] RemyDegenne
assignee:RemyDegenne
26-77096
26 days ago
31-4901
1 month ago
31-5189
31 days
32440 thorimur
author:thorimur
feat: make the `unusedDecidableInType` linter fire when `Decidable*` instances are used only inside of proofs in the type This PR adjusts the `unusedDecidableInType` to prevent false negatives on declarations that only use `Decidable*` hypotheses in proofs that appear in the type. That is, the linter now fires when the `Decidable*` linter is unused outside of proofs. This PR also changes the warning message to be more direct, and indicates when the instance appears only in a proof (vs. not appearing at all). We exempt some deprecated lemmas in `Mathlib.Analysis.Order.Matrix` which the linter now fires on. (Presumably, most prior violations had been cleaned up by #10235, which also detected such lemmas.) Note that this took some tinkering to achieve sufficient performance. We use the following novel(?) "dolorous telescope" strategy (so named due to introducing `sorry`s) to avoid traversing the whole type: - when encountering an instance binder of concern, telescope to create an fvar. - when encountering any other binder, instantiate it with `sorry`. - as we proceed, collect the free variables from these expressions which do not appear in proofs. Since the instances of concern are the only free variables, free variable collection avoids traversing many subexpressions by checking for `hasFVar`, which is a computed field accessible in constant time. Perhaps surprisingly, this is (on net) more performant than using `eraseProofs` and then detecting dependence via bvars. We also implement an `Expr`-level early exit for most types by checking if they bind any instance of concern first. (This adds a very small overhead to types which *do* have an instance of concern, but the check is very fast.) This also adds a profiler category to this linter. Note: we still have yet to optimize (pre)-infotree traversal performance, and have yet to avoid proofs that appear in the value of definitions. However, this PR sets us up to do so. --- ## Notes on performance You might be wondering if this *is* actually a faster strategy, seeing as the bench is quite noisy. To determine this, I made a copy of the linter which I could vary without rebuilding mathlib, and profiled the relevant component locally on all imported declarations in Mathlib by linting the `eoi` token: ```lean module public meta import Lean public import Mathlib.Tactic.Linter.UnusedInstancesInTypeCopy import all Mathlib.Tactic.Linter.UnusedInstancesInTypeCopy open Lean Meta Elab Term Command Mathlib.Linter.UnusedInstancesInType meta section local instance : Insert Name NameSet where insert := fun n s => s.insert n def runCopy : Linter where run stx := do if stx.isOfKind ``Parser.Command.eoi then let opts := (← getOptions).setBool `profiler true let consts := (← getEnv).constants.map₁ -- The following expose private decls in their types, so break `MetaM` methods: let badRecs : NameSet := {`IO.Promise.casesOn, `IO.Promise.recOn, `IO.Promise.rec} profileitM Exception "control" opts do for (n,_) in consts do liftTermElabM do unless n.isInternalDetail || badRecs.contains n do pure () profileitM Exception "bench" opts do for (n,cinfo) in consts do unless n.isInternalDetail || badRecs.contains n do cinfo.toConstantVal.onUnusedInstancesInTypeWhere isDecidableVariant fun _ _ => pure () initialize addLinter runCopy ``` (This could have been done in a `run_cmd`, but I wanted to replicate the circumstances of linting as closely as possible, just in case it introduced mysterious async effects.) Then, in a separate file, I imported `Mathlib` and the above linter, and cycled through reading out the result and editing the underlying component then rebuilding. The control was reliably ~1.07-1.12s. The different strategies came out as follows (the following values are not averaged, but are representative): | | without early exit | with early exit | | ---: | :---: | :---: | | `eraseProofs` | 97.4s | 6.82s | | dolorous telescope | 20.3s | 3.99s | As you can see, the early exit cuts the absolute value (and therefore the absolute difference) down dramatically. But seeing as this lays the groundwork for linting defs and will be used for more linters (with wider scopes, and less early exit opportunities), I think we should opt for the more performant version even though there's some extra complexity. :) [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-linter 199/51 Mathlib/Analysis/Matrix/Order.lean,Mathlib/Lean/Expr/Basic.lean,Mathlib/Tactic/Linter/UnusedInstancesInType.lean,MathlibTest/UnusedInstancesInType.lean 4 29 ['github-actions', 'grunweg', 'leanprover-radar', 'thorimur'] joneugster
assignee:joneugster
25-43890
25 days ago
30-30335
30 days ago
33-61614
33 days
32552 ksenono
author:ksenono
feat(SetTheory/Cardinal): helpers for Konig's theorem --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-set-theory 70/0 Mathlib/SetTheory/Cardinal/Arithmetic.lean,Mathlib/SetTheory/Cardinal/Basic.lean 2 33 ['SnirBroshi', 'b-mehta', 'github-actions', 'ksenono', 'staroperator', 'vihdzp'] b-mehta
assignee:b-mehta
25-28033
25 days ago
31-60876
1 month ago
31-60915
31 days
32600 PrParadoxy
author:PrParadoxy
feat(LinearAlgebra/Multilinear): composition of multilinear maps The composition of a multilinear map with a family of multilinear maps is a multilinear map indexed by a dependent sum. The result reduces to a lemma about the interaction of function application, `Sigma.curry`, and `Function.update`. This variant of `Function.apply_update` is included as `Sigma.apply_curry_update`. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor 40/0 Mathlib/Data/Sigma/Basic.lean,Mathlib/LinearAlgebra/Multilinear/Basic.lean 2 4 ['github-actions', 'goliath-klein', 'kbuzzard'] dwrensha
assignee:dwrensha
24-72904
24 days ago
29-67772
29 days ago
29-68033
29 days
26608 vihdzp
author:vihdzp
feat(SetTheory/Cardinal/Aleph): `o.card ≤ ℵ_ o` and variants --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-set-theory 24/0 Mathlib/SetTheory/Cardinal/Aleph.lean 1 4 ['artie2000', 'github-actions', 'kckennylau', 'leanprover-community-bot-assistant', 'vihdzp'] alreadydone
assignee:alreadydone
22-79444
22 days ago
29-12944
29 days ago
52-76316
52 days
32828 Hagb
author:Hagb
feat(Algebra/Order/Group/Defs): add `IsOrderedAddMonoid.toIsOrderedCancelAddMonoid'` It is similar to `IsOrderedAddMonoid.toIsOrderedCancelAddMonoid`, while with different hypotheses. The conclusion `IsOrderedCancelMonoid α` on `IsOrderedAddMonoid.toIsOrderedCancelAddMonoid` still holds when the hypothesis `CommGroup α` is weakened to `CancelCommMonoid α` while `PartialOrder α` is strengthened to `LinearOrder α`. --- [`IsOrderedAddMonoid.toIsOrderedCancelAddMonoid`](https://leanprover-community.github.io/mathlib4_docs/find/?pattern=IsOrderedAddMonoid.toIsOrderedCancelAddMonoid#doc) and `IsOrderedAddMonoid.toIsOrderedCancelAddMonoid'`: https://github.com/leanprover-community/mathlib4/blob/97f78b1a4311fed1844b94f1c069219a48a098e1/Mathlib/Algebra/Order/Group/Defs.lean#L52-L62 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
4/0 Mathlib/Algebra/Order/Group/Defs.lean 1 1 ['artie2000', 'github-actions'] eric-wieser
assignee:eric-wieser
22-43912
22 days ago
26-33262
26 days ago
26-33294
26 days
31364 YaelDillies
author:YaelDillies
feat: binomial random graphs From LeanCamCombi and formal-conjectures --- - [x] depends on: #31391 - [x] depends on: #31392 - [x] depends on: #31393 - [x] depends on: #31394 - [x] depends on: #31396 - [x] depends on: #31397 - [x] depends on: #31398 - [x] depends on: #31442 - [x] depends on: #31443 - [x] depends on: #31445 - [x] depends on: #31908 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics t-measure-probability 158/0 Mathlib.lean,Mathlib/Probability/Combinatorics/BinomialRandomGraph/Defs.lean,Mathlib/Probability/Combinatorics/README.md 3 9 ['LibertasSpZ', 'YaelDillies', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] EtienneC30
assignee:EtienneC30
21-67634
21 days ago
21-67637
21 days ago
27-64888
27 days
32672 tb65536
author:tb65536
feat: haar measures on short exact sequences This PR defines the notion of a short exact sequence of topological groups, and proves that if `1 → A → B → C → 1` is a short exact sequence of topological groups, then Haar measures on `A` and `C` induce a Haar measure on `B`. The final result of the file is a consequence needed for FLT: If `B → C` is injective on an open set `U`, then `U` has bounded measure. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology t-measure-probability FLT 378/0 Mathlib.lean,Mathlib/MeasureTheory/Measure/Haar/Extension.lean,Mathlib/Topology/Algebra/Group/Extension.lean 3 6 ['RemyDegenne', 'github-actions', 'kbuzzard', 'tb65536'] urkud
assignee:urkud
21-43910
21 days ago
24-64853
24 days ago
28-27955
28 days
32772 tb65536
author:tb65536
feat(Data/Set/Card): criterion for `s.ncard ≤ (f '' s).ncard + 1` This PR gives a criterion `s.ncard ≤ (f '' s).ncard + 1` (note that we always have the inequality `(f '' s).ncard ≤ s.ncard`). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 31/0 Mathlib/Data/Set/Card.lean 1 1 ['github-actions'] pechersky
assignee:pechersky
21-43904
21 days ago
27-26859
27 days ago
27-26833
27 days
32555 ksenono
author:ksenono
feat(Combinatorics/SimpleGraph/Matching): maximum and maximal matchings for Konig's theorem --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics new-contributor 127/1 Mathlib/Combinatorics/SimpleGraph/DegreeSum.lean,Mathlib/Combinatorics/SimpleGraph/Matching.lean 2 8 ['SnirBroshi', 'github-actions', 'ksenono'] awainverse
assignee:awainverse
21-32554
21 days ago
31-59598
1 month ago
31-59627
31 days
32570 ksenono
author:ksenono
feat(Combinatorics/SimpleGraph): bipartite subgraphs and vertex-disjoint graphs for Konig's theorem --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics new-contributor 22/0 Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Combinatorics/SimpleGraph/Subgraph.lean 2 10 ['SnirBroshi', 'github-actions'] kmill
assignee:kmill
21-32094
21 days ago
31-36397
1 month ago
31-36437
31 days
31925 alreadydone
author:alreadydone
feat(Topology): étalé space associated to a predicate on sections --- migrated from #22782 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology 899/164 Mathlib.lean,Mathlib/AlgebraicGeometry/ProjectiveSpectrum/StructureSheaf.lean,Mathlib/Data/Set/Operations.lean,Mathlib/Geometry/Manifold/Sheaf/Smooth.lean,Mathlib/Logic/Equiv/Basic.lean,Mathlib/Topology/EtaleSpace.lean,Mathlib/Topology/IsLocalHomeomorph.lean,Mathlib/Topology/Sheaves/LocalPredicate.lean,Mathlib/Topology/Sheaves/Sheafify.lean,Mathlib/Topology/Sheaves/Stalks.lean 10 13 ['adamtopaz', 'alreadydone', 'github-actions', 'mathlib4-merge-conflict-bot'] adamtopaz
assignee:adamtopaz
20-67356
20 days ago
20-71328
20 days ago
25-66811
25 days
32679 YaelDillies
author:YaelDillies
chore(Data/Sym2): improve defeq of `diagSet` #30559 introduced a regression on the defeqs in the `SimpleGraph` API. This PR fixes it. From LeanCamCombi --- I personally think this new `diagSet` definition is unnecessary: `{e | e.IsDiag}` is not much longer to write than `Sym2.diagSet` and more transparent, but whatever. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 52/41 Mathlib/Combinatorics/SimpleGraph/Basic.lean,Mathlib/Combinatorics/SimpleGraph/DeleteEdges.lean,Mathlib/Combinatorics/SimpleGraph/Operations.lean,Mathlib/Data/Sym/Card.lean,Mathlib/Data/Sym/Sym2.lean 5 9 ['SnirBroshi', 'YaelDillies', 'b-mehta', 'github-actions', 'mathlib4-merge-conflict-bot', 'vihdzp'] pechersky
assignee:pechersky
20-55518
20 days ago
20-55582
20 days ago
29-177
29 days
32355 bjornsolheim
author:bjornsolheim
feat(Geometry/Convex/Cone): define and characterize simplicial pointed cones Define finitely generated and simplicial pointed cones. Prove lemmas about simplicial (and generating simplicial) cones # Notes * I have tried alternative implementations (finite, finset, structure) If one can live with the extensional quantifier the finset seems better. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-convex-geometry 118/0 Mathlib.lean,Mathlib/Geometry/Convex/Cone/Simplicial.lean 2 1 ['github-actions'] nobody
20-48171
20 days ago
20-48663
20 days ago
30-53275
30 days
33028 bjornsolheim
author:bjornsolheim
feat(Geometry/Convex/Cone): minimal and maximal cone tensor products are commutative Prove that the minimal and maximal cone tensor products are commutative. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-convex-geometry 57/0 Mathlib/Geometry/Convex/Cone/TensorProduct.lean 1 1 ['github-actions'] nobody
20-8100
20 days ago
21-36511
21 days ago
21-36553
21 days
31425 robertmaxton42
author:robertmaxton42
feat(Topology): implement delaborators for non-standard topology notation Add delaborators for unary and binary notation related to non-standard topologies in the TopologicalSpace namespace. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology 104/0 Mathlib.lean,Mathlib/Topology/Defs/Basic.lean,Mathlib/Util/DelabNonCanonical.lean,MathlibTest/Delab/TopologicalSpace.lean 4 31 ['eric-wieser', 'github-actions', 'jcommelin', 'kckennylau', 'robertmaxton42'] PatrickMassot
assignee:PatrickMassot
19-80787
19 days ago
45-22450
1 month ago
45-53338
45 days
32532 SnirBroshi
author:SnirBroshi
feat(Combinatorics/SimpleGraph/Connectivity): connected components are maximally connected subsets/subgraphs --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 32/0 Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Subgraph.lean 2 2 ['github-actions', 'mathlib4-merge-conflict-bot'] awainverse
assignee:awainverse
19-52135
19 days ago
19-52161
19 days ago
32-21107
32 days
30872 rudynicolop
author:rudynicolop
feat(Computability/NFA): NFA closure under concatenation This PR proves that regular languages are closed under concatenation via a direct construction on `NFA`s without `εNFA` nor ε-transitions. The main new definitions and results include: - `M1.concat M2`, the concatenation of `NFA`s `M1` and `M2`, a direct construction without ε-transitions. - Theorem `accepts_concat : (M1.concat M2).accepts = M1.accepts * M2.accepts`, showing the correctness of the construction. - Theorem `IsRegular.mul`, showing that regular languages are closed under concatenation. --- - [x] depends on: #31038 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-computability maintainer-merge 104/7 Mathlib/Computability/NFA.lean 1 63 ['YaelDillies', 'ctchou', 'github-actions', 'lambda-fairy', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'rudynicolop'] YaelDillies
assignee:YaelDillies
19-51870
19 days ago
20-32325
20 days ago
38-44225
38 days
31960 urkud
author:urkud
feat: a lower bound for the volume of a cone on the unit sphere --- - [x] depends on: #31956 - [x] depends on: #31957 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability 95/0 Mathlib/MeasureTheory/Constructions/HaarToSphere.lean 1 6 ['PatrickMassot', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'urkud'] hrmacbeth
assignee:hrmacbeth
19-50702
19 days ago
43-56917
1 month ago
43-59460
43 days
32260 jsm28
author:jsm28
feat(Geometry/Euclidean/Angle/Oriented/Affine): oriented angle bisection and halving unoriented angles Add lemmas relating points bisecting an oriented angle to explicit expressions for one unoriented angle in relation to half another unoriented angle. --- Feel free to golf. --- - [ ] depends on: #32259 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-euclidean-geometry 157/0 Mathlib/Geometry/Euclidean/Angle/Oriented/Affine.lean 1 3 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] JovanGerb
assignee:JovanGerb
19-43920
19 days ago
22-55483
22 days ago
22-57987
22 days
32541 YaelDillies
author:YaelDillies
chore: import Tactic.Attr.Register privately This is mostly to start a discussion: Should basic tactic files like this one be re-exported by all files out of them being basic, or whether they should be explicitly imported by the few files that actually need it. Eg in #32245 Andrew and I are adding a new simp attribute, and it's a bit silly that we have to rebuild all of mathlib because that file is re-exported everywhere. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) large-import 43/9 Mathlib/Algebra/Free.lean,Mathlib/CategoryTheory/Monoidal/Mon_.lean,Mathlib/Control/Applicative.lean,Mathlib/Control/Basic.lean,Mathlib/Control/Functor.lean,Mathlib/Control/Monad/Basic.lean,Mathlib/Control/Traversable/Basic.lean,Mathlib/Control/Traversable/Equiv.lean,Mathlib/Control/Traversable/Lemmas.lean,Mathlib/Data/Prod/Basic.lean,Mathlib/Data/Set/Operations.lean,Mathlib/Logic/Basic.lean,Mathlib/Logic/Equiv/Defs.lean,Mathlib/Logic/Function/Basic.lean,Mathlib/Logic/Function/Defs.lean,Mathlib/Logic/Nontrivial/Basic.lean,Mathlib/Tactic/Attr/Core.lean,Mathlib/Tactic/HigherOrder.lean,Mathlib/Tactic/Zify.lean 19 5 ['EtienneC30', 'YaelDillies', 'artie2000', 'github-actions'] kex-y
assignee:kex-y
19-43919
19 days ago
31-72479
1 month ago
31-82768
31 days
32826 felixpernegger
author:felixpernegger
feat(Data/Tuple/Sort): Permutation is monotone iff its the identity Sort of permutation is its inverse + Permutation is monotone iff its the identity new-contributor t-data 19/0 Mathlib/Data/Fin/Tuple/Sort.lean 1 1 ['github-actions'] TwoFX
assignee:TwoFX
19-43916
19 days ago
26-37030
26 days ago
26-37035
26 days
32127 CoolRmal
author:CoolRmal
feat: use IndexedPartition.piecewise to create simple/measurable/strongly measurable functions The lemmas proved in this PR are needed in https://github.com/RemyDegenne/brownian-motion/pull/304. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability large-import brownian 111/4 Mathlib/Data/Setoid/Partition.lean,Mathlib/MeasureTheory/Function/SimpleFunc.lean,Mathlib/MeasureTheory/Function/StronglyMeasurable/Basic.lean,Mathlib/MeasureTheory/MeasurableSpace/Basic.lean 4 21 ['CoolRmal', 'EtienneC30', 'github-actions', 'hanwenzhu', 'mathlib4-merge-conflict-bot'] EtienneC30
assignee:EtienneC30
19-9651
19 days ago
19-9710
19 days ago
40-75031
40 days
32144 EtienneC30
author:EtienneC30
feat: add a predicate HasGaussianLaw Define a predicate `HasGaussianLaw X P`, which states that under the measure `P`, the random variable `X` has a Gaussian distribution, i.e. `IsGaussian (P.map X)`. --- - [x] depends on: #32280 - [x] depends on: #32719 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability brownian 279/0 Mathlib.lean,Mathlib/Probability/Distributions/Gaussian/HasGaussianLaw/Basic.lean,Mathlib/Probability/Distributions/Gaussian/HasGaussianLaw/Def.lean 3 6 ['EtienneC30', 'RemyDegenne', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] kex-y
assignee:kex-y
18-74041
18 days ago
20-11825
20 days ago
34-12743
34 days
32702 SnirBroshi
author:SnirBroshi
chore(Combinatorics/SimpleGraph/Connectivity): move `Finite ConnectedComponent` instance from `WalkCounting.lean` to `Connected.lean` --- This moves it near similar instances, and makes it available for more files. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 1/2 Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/WalkCounting.lean 2 1 ['github-actions', 'vlad902'] awainverse
assignee:awainverse
18-43890
18 days ago
28-56184
28 days ago
28-56218
28 days
32739 Rida-Hamadani
author:Rida-Hamadani
chore(SimpleGraph): golf and improve style of `Subwalks.lean` maintaining the sub-walks file after the walk split, golfing some proofs --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 11/18 Mathlib/Combinatorics/SimpleGraph/Walks/Subwalks.lean 1 1 ['github-actions', 'vlad902'] awainverse
assignee:awainverse
18-43889
18 days ago
27-78311
27 days ago
27-78389
27 days
32910 felixpernegger
author:felixpernegger
feat(Data/Nat/Choose): two binomial coefficient sum identities This PR proves two well-known sum identities around binomial coefficients. While there are probably hundreds of such identities, these two seem to be well known enough to be in mathlib (i.e. are mentioned in the Wikipedia [article](https://en.wikipedia.org/wiki/Binomial_coefficient#math_8) about binomial coefficients). new-contributor t-data 31/0 Mathlib/Data/Nat/Choose/Sum.lean,Mathlib/Data/Nat/Choose/Vandermonde.lean 2 1 ['github-actions'] TwoFX
assignee:TwoFX
18-43886
18 days ago
23-79862
23 days ago
23-80188
23 days
32989 kim-em
author:kim-em
fix(Tactic/Simps): skip @[defeq] inference for non-exposed definitions This PR makes `@[simps]` check whether the source definition's body is exposed before calling `inferDefEqAttr`. When the body is not exposed, we skip the `@[defeq]` inference to avoid validation errors. Without this fix, using `@[simps]` on a definition that is not `@[expose]`d produces an error like: ``` Theorem Foo_bar has a `rfl`-proof and was thus inferred to be `@[defeq]`, but validating that attribute failed: Not a definitional equality: the left-hand side ... is not definitionally equal to the right-hand side ... Note: This theorem is exported from the current module. This requires that all definitions that need to be unfolded to prove this theorem must be exposed. ``` The fix checks `(← getEnv).setExporting true |>.find? cfg.srcDeclName |>.any (·.hasValue)` to determine if the definition body is visible in the public scope, and only calls `inferDefEqAttr` if it is. 🤖 Prepared with Claude Code t-meta 40/2 Mathlib/Tactic/Simps/Basic.lean,MathlibTest/SimpsModule.lean 2 8 ['JovanGerb', 'github-actions', 'kim-em'] eric-wieser
assignee:eric-wieser
18-43885
18 days ago
22-34692
22 days ago
22-34728
22 days
33016 xgenereux
author:xgenereux
feat: RingHom.adjoinAlgebraMap Consider a tower of rings `A / B / C` and `b : B`, then there is a natural map from `A[b]` to `A[algebraMap B C b]` (adjoin `b` viewed as an element of `C`). This PR adds 3 versions, depending on whether we use `Algebra.adjoin` or `IntermediateField.adjoin`: - `Algebra.RingHom.adjoinAlgebraMap : Algebra.adjoin A {b} →+* Algebra.adjoin A {(algebraMap B C) b}` - `IntermediateField.RingHom.adjoinAlgebraMapOfAlgebra : Algebra.adjoin A {b} →+* A⟮((algebraMap B C) b)⟯` - `IntermediateField.RingHom.adjoinAlgebraMap : A⟮b⟯ →+* A⟮((algebraMap B C) b)⟯` Note: We create a new file for `Algebra.RingHom.adjoinAlgebraMap`, which is intended for results about adjoining singletons, because it is convenient to import `Algebra.Adjoin.Polynomial`. Co-authored-by: María Inés de Frutos Fernández <[mariaines.dff@gmail.com](mailto:mariaines.dff@gmail.com)> --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 103/0 Mathlib.lean,Mathlib/FieldTheory/IntermediateField/Adjoin/Algebra.lean,Mathlib/FieldTheory/IntermediateField/Adjoin/Defs.lean,Mathlib/RingTheory/Adjoin/Singleton.lean 4 1 ['github-actions'] bryangingechen
assignee:bryangingechen
18-43882
18 days ago
21-54385
21 days ago
21-54358
21 days
30898 vihdzp
author:vihdzp
feat: characterization of `List.splitBy` --- - [x] depends on: #30892 Moved from #16837. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 110/10 Mathlib/Data/List/Flatten.lean,Mathlib/Data/List/SplitBy.lean 2 6 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'vihdzp'] TwoFX
assignee:TwoFX
18-37916
18 days ago
18-37940
18 days ago
27-80005
27 days
28796 grunweg
author:grunweg
feat: immersions are smooth The conventional textbook definition demands that an immersion be smooth. When asking for the immersion to have local slice charts (as we do), this implies smoothness automatically. --- - [x] depends on: #28701 - [x] depends on: #28793 - [x] depends on: #30356 - [x] depends on: #28853 (for simplicity) [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-differential-geometry 198/15 Mathlib/Analysis/Calculus/ContDiff/Basic.lean,Mathlib/Geometry/Manifold/ContMDiff/Atlas.lean,Mathlib/Geometry/Manifold/Immersion.lean,Mathlib/Geometry/Manifold/IsManifold/ExtChartAt.lean,Mathlib/Geometry/Manifold/LocalSourceTargetProperty.lean,Mathlib/Geometry/Manifold/SmoothEmbedding.lean 6 25 ['chrisflav', 'github-actions', 'grunweg', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] PatrickMassot
assignee:PatrickMassot
17-43892
17 days ago
20-75224
20 days ago
20-82546
20 days
31315 Parcly-Taxel
author:Parcly-Taxel
feat: IMO 2010 Q5 See [#general > Panic in rw: Nat.pow exponent is too big @ 💬](https://leanprover.zulipchat.com/#narrow/channel/113488-general/topic/Panic.20in.20rw.3A.20Nat.2Epow.20exponent.20is.20too.20big/near/513294906) and leanprover/lean4#11713 for why 2010 and 11 are replaced with variables. maintainer-merge IMO 245/0 Archive.lean,Archive/Imo/Imo2010Q5.lean 2 6 ['Parcly-Taxel', 'github-actions', 'jsm28', 'nomeata'] jsm28
assignee:jsm28
17-43891
17 days ago
20-48177
20 days ago
42-45256
42 days
33052 JovanGerb
author:JovanGerb
feat: replace `rw??` tactic with `#infoview_search` command This PR introduces the `#infoview_search` command. It gives an improved way of interacting with the library search from `rw??`, and hence this PR also deprecates `rw??` (`rw??` still works, but it displays a warning message suggesting to use `#infoview_search` instead). The difference is that `#infoview_search` is a command, so you type it once, and then you can use rewrite search in any tactic state in any place. This is more convenient than having to write out `rw??` every time. I have many improvements planned for `#infoview_search`, but this PR simply gives it the same capabilities that `rw??` currently has. One of those improvements is to also do `apply` search, and `apply at` search. That is why the name doesn't contain `rw` anymore. To prepare for more code developments around `#infoview_search`, I've moved the relevant files into a new folder `Mathlib.Tactic.InfoviewSearch`. Note that one annoyance with writing `#infoview_search` is that there is a linter warning. Should I remove the `#` from the command, or are we happy with this? ``` `#`-commands, such as '#infoview_search', are not allowed in 'Mathlib' Note: This linter can be disabled with `set_option linter.hashCommand false` ``` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta file-removed 100/59 Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/Common.lean,Mathlib/Tactic/InfoviewSearch/InteractiveUnfold.lean,Mathlib/Tactic/InfoviewSearch/LibraryRewrite.lean,MathlibTest/LibraryRewrite.lean 6 1 ['github-actions'] adamtopaz
assignee:adamtopaz
17-43883
17 days ago
20-68956
20 days ago
20-69006
20 days
26484 peabrainiac
author:peabrainiac
feat(Geometry/Diffeology): basics of diffeological spaces Introduces diffeological spaces, smooth maps between them, the D-topology and the standard diffeology on finite-dimensional normed spaces. --- This PR continues the work from #21969. t-differential-geometry 491/0 Mathlib.lean,Mathlib/Geometry/Diffeology/Basic.lean,docs/references.bib 3 12 ['JovanGerb', 'github-actions', 'grunweg', 'lecopivo', 'mathlib4-merge-conflict-bot', 'peabrainiac'] ocfnash
assignee:ocfnash
17-13106
17 days ago
18-47775
18 days ago
156-79463
156 days
32021 jsm28
author:jsm28
feat(Geometry/Euclidean/Altitude): `map` and `restrict` lemmas Add lemmas about `altitude`, `altitudeFoot` and `height` for simplices mapped under an affine isometry or restricted to an affine subspace. --- - [x] depends on: #32016 - [x] depends on: #32017 - [ ] depends on: #32019 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-euclidean-geometry 75/0 Mathlib/Geometry/Euclidean/Altitude.lean 1 4 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] JovanGerb
assignee:JovanGerb
16-43908
16 days ago
19-69918
19 days ago
19-69977
19 days
33031 chiyunhsu
author:chiyunhsu
feat(Combinatorics/Enumerative/Partition): add combinatorial proof of Euler's partition theorem The new file EulerComb.lean contains the combinatorial proof of Euler's partition theorem. The analytic proof of the theorem and its generalization of Glaisher's Theorem has already been formalized in [Glaisher.lean](https://github.com/leanprover-community/mathlib4/blob/master/Mathlib/Combinatorics/Enumerative/Partition/Glaisher.lean). The generalization of the combinatorial proof from this file to Glaisher's Theorem is within reach. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics new-contributor 531/0 Mathlib.lean,Mathlib/Combinatorics/Enumerative/Partition/EulerComb.lean 2 5 ['chiyunhsu', 'github-actions', 'tb65536', 'vihdzp'] b-mehta
assignee:b-mehta
16-43905
16 days ago
21-21430
21 days ago
21-21470
21 days
33044 bryangingechen
author:bryangingechen
ci: also get cache for parent commit cf. https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Mathlib.20has.20moved.20to.20the.20new.20module.20system/near/563452000 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) CI 84/8 .github/build.in.yml,.github/workflows/bors.yml,.github/workflows/build.yml,.github/workflows/build_fork.yml 4 7 ['bryangingechen', 'github-actions', 'jcommelin', 'mathlib-bors'] joneugster
assignee:joneugster
16-43903
16 days ago
19-54730
19 days ago
20-30075
20 days
33063 DavidLedvinka
author:DavidLedvinka
chore(Probability): Rename Adapted to StronglyAdapted See discussion at: https://leanprover.zulipchat.com/#narrow/channel/509433-Brownian-motion/topic/Adapted.20Filtrations.20for.20Markov.20Chains.20and.20Markov.20Processes t-measure-probability 328/224 Mathlib/Probability/Kernel/Disintegration/Density.lean,Mathlib/Probability/Martingale/Basic.lean,Mathlib/Probability/Martingale/BorelCantelli.lean,Mathlib/Probability/Martingale/Centering.lean,Mathlib/Probability/Martingale/Convergence.lean,Mathlib/Probability/Martingale/OptionalSampling.lean,Mathlib/Probability/Martingale/OptionalStopping.lean,Mathlib/Probability/Martingale/Upcrossing.lean,Mathlib/Probability/Moments/SubGaussian.lean,Mathlib/Probability/Process/Adapted.lean,Mathlib/Probability/Process/HittingTime.lean,Mathlib/Probability/Process/Predictable.lean,Mathlib/Probability/Process/Stopping.lean 13 9 ['DavidLedvinka', 'EtienneC30', 'github-actions'] EtienneC30
assignee:EtienneC30
16-43902
16 days ago
19-47372
19 days ago
20-6915
20 days
33082 AntoineChambert-Loir
author:AntoineChambert-Loir
feat(GroupTheory/SpecificGroups/Alternating/Simple): the alternating group on at least 5 letters is simple. This is the conclusion of the story of the proof of simplicity of the alternating group using the Iwasawa criterion. * `Equiv.Perm.iwasawaStructure_two`: the natural `IwasawaStructure` of `Equiv.Perm α` acting on `Nat.Combination α 2` Its commutative subgroups consist of the permutations with support in a given element of `Nat.Combination α 2`. They are cyclic of order 2. * `alternatingGroup_of_le_of_normal`: If `α` has at least 5 elements, then a nontrivial normal subgroup of `Equiv.Perm α` contains the alternating group. * `alternatingGroup.iwasawaStructure_three`: the natural `IwasawaStructure` of `alternatingGroup α` acting on `Nat.Combination α 3` Its commutative subgroups consist of the permutations with support in a given element of `Nat.Combination α 2`. They are cyclic of order 3. * `alternatingGroup.iwasawaStructure_three`: the natural `IwasawaStructure` of `alternatingGroup α` acting on `Nat.Combination α 4` Its commutative subgroups consist of the permutations of cycleType (2, 2) with support in a given element of `Nat.Combination α 2`. They have order 4 and exponent 2 (`IsKleinFour`). * `alternatingGroup.normal_subgroup_eq_bot_or_eq_top`: If `α` has at least 5 elements, then a nontrivial normal subgroup of `alternatingGroup` is `⊤`. * `alternatingGroup.isSimpleGroup`: If `α` has at least 5 elements, then `alternatingGroup α` is a simple group. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) large-import t-group-theory 821/13 Mathlib.lean,Mathlib/GroupTheory/GroupAction/SubMulAction/Combination.lean,Mathlib/GroupTheory/Perm/Cycle/Type.lean,Mathlib/GroupTheory/Perm/Support.lean,Mathlib/GroupTheory/SpecificGroups/Alternating.lean,Mathlib/GroupTheory/SpecificGroups/Alternating/Simple.lean,Mathlib/GroupTheory/SpecificGroups/KleinFour.lean 7 1 ['github-actions'] mattrobball
assignee:mattrobball
16-43900
16 days ago
20-2422
20 days ago
20-2465
20 days
33109 felixpernegger
author:felixpernegger
feat(Data/Nat/Choose): Binomial inversion This PR adds binomial inversion (also called binomial transform), which is a useful method for proving binomial identities. It is tricky to find direct references to binomial inversion, but for example [this](https://en.wikipedia.org/wiki/Binomial_transform#Binomial_convolution) Wikipedia article mentions it ("The formula"). The first theorem ```alternating_sum_choose_mul_of_alternating_sum_choose_mul``` could be refined (we only need the hypothesis ```h``` up to some point), but this seems to needlessly complicate it. new-contributor 107/0 Mathlib.lean,Mathlib/Data/Nat/Choose/Inversion.lean 2 4 ['felixpernegger', 'github-actions', 'wwylele'] dagurtomas
assignee:dagurtomas
16-43895
16 days ago
19-57227
19 days ago
19-57208
19 days
26614 Rida-Hamadani
author:Rida-Hamadani
feat(SimpleGraph): add more API for `take`/`drop` The main lemma proves that taking `n` vertices of a walk results in a sub-walk of taking `k` vertices when `n` is less than or equal to `k`, alongside a similar lemma for dropping vertices. --- - [x] depends on: #26655 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 58/0 Mathlib/Combinatorics/SimpleGraph/Walks/Operations.lean,Mathlib/Combinatorics/SimpleGraph/Walks/Subwalks.lean 2 20 ['Rida-Hamadani', 'b-mehta', 'github-actions', 'leanprover-community-bot-assistant', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] nobody
16-38142
16 days ago
16-39908
16 days ago
21-37025
21 days
33214 JJYYY-JJY
author:JJYYY-JJY
chore(Data/List/Rotate): add simp attributes * Refs #7987 (SC: Data/List/Rotate) * Add `@[simp]` to: `rotate_mod`, `rotate'_nil`, `rotate'_rotate'`, `rotate'_mod`, `rotate_rotate`, `getElem?_rotate`, `getElem_rotate`, `head?_rotate`, `map_rotate`. * Verification: `lake build Mathlib.Data.List.Rotate`. new-contributor t-data 7/0 Mathlib/Data/List/Rotate.lean 1 1 ['github-actions'] nobody
16-26228
16 days ago
16-37828
16 days ago
16-37868
16 days
33126 CoolRmal
author:CoolRmal
feat: function composition preserves boundedness This PR adds the following theorem: if the range of a function `g` is bounded above, then `g ∘ f` is bounded above for all functions `f`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-order 12/0 Mathlib/Order/Bounds/Basic.lean 1 1 ['github-actions'] bryangingechen
assignee:bryangingechen
15-43896
15 days ago
19-1539
19 days ago
19-1578
19 days
33128 gasparattila
author:gasparattila
feat(Topology/UniformSpace): generalize `TotallyBounded` to filters Some of these generalizations will be useful for showing the completeness of `TopologicalSpace.Compacts` in a non-metrizable setting. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology 156/54 Mathlib/Data/Rel.lean,Mathlib/Topology/UniformSpace/Cauchy.lean,Mathlib/Topology/UniformSpace/UniformEmbedding.lean 3 1 ['github-actions'] dagurtomas
assignee:dagurtomas
15-43895
15 days ago
18-53991
18 days ago
18-78524
18 days
33129 Paul-Lez
author:Paul-Lez
feat(Tactic/Simproc/VecPerm): Add simproc for permuting entries of a vector --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta 127/0 Mathlib.lean,Mathlib/Tactic.lean,Mathlib/Tactic/Simproc/VecPerm.lean,MathlibTest/Simproc/VecPerm.lean 4 7 ['JovanGerb', 'github-actions'] thorimur
assignee:thorimur
15-43894
15 days ago
18-73377
18 days ago
18-76406
18 days
33253 SnirBroshi
author:SnirBroshi
feat(Combinatorics/SimpleGraph/Clique): avoid `Fintype`/`Finite` assumptions where possible Also prove `G.cliqueNum ≤ G.chromaticNumber` without any finiteness assumptions. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 39/40 Mathlib/Combinatorics/SimpleGraph/Clique.lean,Mathlib/Combinatorics/SimpleGraph/Coloring.lean 2 1 ['github-actions'] nobody
15-2336
15 days ago
15-2348
15 days ago
15-2381
15 days
31794 thorimur
author:thorimur
feat: `unusedFintypeInType` linter Adds an `UnusedInstancesInType` linter which suggests replacing `Fintype` instances with `Finite` or removing them. This linter is off by default: it is turned on in #31795. The violations found by this linter are fixed in #33068 (merged) and #33148 (merged). Note that the portion of this diff corresponding to the actual linter file is relatively small (+68 -11), and is very similar to the `unusedDecidableInType` linter. The majority of the diff in the linter file itself is factoring out the workaround to lean4#11313 (which is used in both linters); the rest of the diff comes from reorganizing tests and adding tests. --- - [x] depends on: #31142 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) file-removed 304/46 Mathlib/Tactic/Linter/UnusedInstancesInType.lean,MathlibTest/UnusedInstancesInType/Basic.lean,MathlibTest/UnusedInstancesInType/Decidable.lean,MathlibTest/UnusedInstancesInType/Fintype.lean,MathlibTest/UnusedInstancesInType/FintypeNeedingImport.lean,MathlibTest/UnusedInstancesInType/SetOption.lean 6 11 ['JovanGerb', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'thorimur'] JovanGerb
assignee:JovanGerb
14-75052
14 days ago
18-48677
18 days ago
35-67818
35 days
33254 SnirBroshi
author:SnirBroshi
feat(Data/Nat/Lattice): `¬BddAbove s → sSup s = 0` --- Note that it can also be proven `by simp [h]` after the `ConditionallyCompleteLinearOrderBot` instance below it. The theorem name matches the same theorems for other types: `Int.csSup_of_not_bdd_above`, `Real.sSup_of_not_bddAbove`, `NNReal.sSup_of_not_bddAbove`. Also renamed related `Int` theorems to conform to the naming conventions. [Zulip](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/.60.C2.ACBddAbove.20s.20.E2.86.92.20sSup.20s.20.3D.200.60/with/565275221) [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 15/4 Mathlib/Data/Int/ConditionallyCompleteOrder.lean,Mathlib/Data/Nat/Lattice.lean 2 3 ['SnirBroshi', 'github-actions', 'vihdzp'] nobody
14-65518
14 days ago
15-1824
15 days ago
15-1859
15 days
32160 SnirBroshi
author:SnirBroshi
feat(Combinatorics/SimpleGraph/Walks): helper theorems about `darts` and `support` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 33/1 Mathlib/Combinatorics/SimpleGraph/Walks/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Walks/Traversal.lean 2 1 ['github-actions'] kmill
assignee:kmill
14-59558
14 days ago
42-41526
1 month ago
42-41556
42 days
33147 SnirBroshi
author:SnirBroshi
feat(Combinatorics/SimpleGraph/Coloring): add a few missing instances (`IsEmpty`/`Nontrivial`/`Infinite`) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 22/0 Mathlib/Combinatorics/SimpleGraph/Coloring.lean,Mathlib/Combinatorics/SimpleGraph/Maps.lean 2 1 ['github-actions'] b-mehta
assignee:b-mehta
14-43910
14 days ago
18-37044
18 days ago
18-37088
18 days
31092 FlAmmmmING
author:FlAmmmmING
feat(Algebra/Group/ForwardDiff.lean): Add theorem `sum_shift_eq_fwdDiff_iter`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra new-contributor
label:t-algebra$
17/1 Mathlib/Algebra/Group/ForwardDiff.lean 1 18 ['BeibeiX0', 'FlAmmmmING', 'Ruben-VandeVelde', 'dagurtomas', 'github-actions', 'mathlib4-merge-conflict-bot'] dagurtomas
assignee:dagurtomas
14-19278
14 days ago
14-19302
14 days ago
40-15931
40 days
33121 SnirBroshi
author:SnirBroshi
feat(Combinatorics/SimpleGraph/Hasse): paths in a graph are isomorphic to path graphs --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics large-import 38/1 Mathlib/Combinatorics/SimpleGraph/Hasse.lean 1 1 ['github-actions'] b-mehta
assignee:b-mehta
14-5479
14 days ago
19-13497
19 days ago
19-13536
19 days
33211 Komyyy
author:Komyyy
doc(Order/Filter/*): outdated documents `f ×ˢ g` is not an notation of `Filter.prod` anymore, but [a notation class](https://leanprover-community.github.io/mathlib4_docs/Mathlib/Order/Filter/Defs.html#Filter.instSProd). Also, some definitions were moved to `Mathlib.Order.Filter.Defs`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) documentation t-order 6/10 Mathlib/Order/Filter/Curry.lean,Mathlib/Order/Filter/Pi.lean,Mathlib/Order/Filter/Prod.lean 3 6 ['Komyyy', 'github-actions', 'plp127'] bryangingechen
assignee:bryangingechen
13-43899
13 days ago
16-47485
16 days ago
16-47461
16 days
32745 LTolDe
author:LTolDe
feat(Topology/Algebra): add MulActionConst.lean add Topology/Algebra/MulActionConst.lean introduce class `ContinuousSMulConst` for a scalar multiplication that is continuous in the first argument, in analogy to `ContinuousConstSMul` define `MulAction.ball x U` as the set `U • {x}` given `[SMul G X] (x : X) (U : Set G)` The lemmas shown here will be useful to prove the **Effros Theorem**, see [zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Effros.20Theorem/with/558712441). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology new-contributor 98/0 Mathlib.lean,Mathlib/Topology/Algebra/MulActionConst.lean 2 1 ['github-actions'] dagurtomas
assignee:dagurtomas
12-43912
12 days ago
27-73636
27 days ago
27-73686
27 days
32971 Paul-Lez
author:Paul-Lez
feat(Data/Finsupp/Pointwise): generalise pointwise scalar multiplication of finsupps This PR continues the work from #24050. Original PR: https://github.com/leanprover-community/mathlib4/pull/24050 t-data 7/4 Mathlib/Data/Finsupp/Pointwise.lean 1 2 ['Paul-Lez', 'github-actions'] pechersky
assignee:pechersky
12-43908
12 days ago
22-72640
22 days ago
22-72676
22 days
33236 JovanGerb
author:JovanGerb
refactor(translate): merge `expand` into `applyReplacementFun` This PR refactors the main translation loop of `to_additive `/`to_dual` so that it operates on free variables instead of loose bound variables. This will make it much easier to implement the reordering of arguments of arguments, which is something we need for `to_dual`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta 95/78 Mathlib/Tactic/Translate/Core.lean,MathlibTest/toAdditive.lean 2 4 ['JovanGerb', 'github-actions', 'leanprover-radar'] joneugster
assignee:joneugster
12-43905
12 days ago
15-73555
15 days ago
15-73594
15 days
33248 vihdzp
author:vihdzp
refactor(MeasureTheory/Measure/Stieltjes): simpler definition of `botSet` --- Arguably we could get rid of `botSet` altogether, but in either case this is still an improvement. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability 13/19 Mathlib/MeasureTheory/Measure/Stieltjes.lean 1 1 ['github-actions'] EtienneC30
assignee:EtienneC30
12-43904
12 days ago
15-45299
15 days ago
15-45335
15 days
33292 SnirBroshi
author:SnirBroshi
feat(Combinatorics/SimpleGraph/LineGraph): lift copies/isomorphisms to line-graph --- Non-injective homomorphisms (`G →g G'`) cannot be lifted to a homomorphism on line-graphs (`G.lineGraph →g G'.lineGraph`) because e.g. `∀ k > 1` there is a homomorphism from `pathGraph k` to `G'` iff `G'` has an edge, and `∀ n > 0, (pathGraph (n + 1)).lineGraph ≃ pathGraph n`, but there is no homomorphism from `pathGraph k` to `pathGraph 1` because it has no edges. So for `G := pathGraph 3` and `G' := pathGraph 2` there is a `G →g G'` but no `G.lineGraph →g G'.lineGraph`. But we can lift `Copy`/`Embedding`/`Iso`. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics large-import 47/4 Mathlib/Combinatorics/SimpleGraph/LineGraph.lean,Mathlib/Data/Sym/Sym2.lean 2 1 ['github-actions'] nobody
12-24994
12 days ago
12-81542
12 days ago
13-49979
13 days
32987 kim-em
author:kim-em
feat: pipeline downloads and decompression in `cache get` This PR modifies `lake exe cache get` to decompress files as they download, rather than waiting for all downloads to complete first. Previously the cache system had two sequential phases: download all files using `curl --parallel`, then decompress all files using a single `leantar` call. Now a background task spawns sequential batched `leantar` calls to decompress files as downloads complete, pipelining network I/O and disk I/O. 🤖 Prepared with Claude Code 194/30 Cache/Requests.lean 1 1 ['github-actions'] dagurtomas
assignee:dagurtomas
11-43874
11 days ago
22-45020
22 days ago
22-44993
22 days
33206 lua-vr
author:lua-vr
feat(Integral.Bochner.Set): add `tendsto_setIntegral_of_monotone₀` Adds the lemma `tendsto_setIntegral_of_monotone₀`, a version of `tendsto_setIntegral_of_monotone` requiring only `AEMeasurableSet` in the hypothesis. The previous version is redefined as a specialization. Also renames `integral_union_ae` to `setIntegral_union₀` for consistency with the rest of the library (it matches the existing `setIntegral_union`). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability 27/13 Mathlib/MeasureTheory/Integral/Bochner/Set.lean 1 2 ['github-actions', 'mathlib4-merge-conflict-bot'] RemyDegenne
assignee:RemyDegenne
10-69995
10 days ago
10-70020
10 days ago
16-2581
16 days
33363 BoltonBailey
author:BoltonBailey
feat: add `empty_eq_image` simp lemmas Creates new simp lemmas `image_eq_empty`, similar to existing simp lemmas, but with the LHS equality reversed, so that simp can identify these when in this form. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 7/0 Mathlib/Data/Finset/Image.lean,Mathlib/Data/Set/Image.lean 2 1 ['github-actions'] nobody
10-50717
10 days ago
10-50744
10 days ago
10-50782
10 days
29788 robertmaxton42
author:robertmaxton42
feat(Topology): adds bundled continuous maps for sum, sigma, subtype, mapsto, inclusion Adds a collection of bundled continuous maps and homeomorphisms, and helper lemmas for working with their compositions. Bundling of existing continuity lemmas: * `ContinuousMap.subtypeVal` * `ContinuousMap.inl` and `.inr`; `ContinuousMap.sum` bundles `Continuous.sumElim`; `ContinuousMap.sumMap`, which is a quotient map when both components are quotient maps * `ContinuousMap.sigmaMap`, which is a quotient map when given a family of quotient maps * `ContinuousMap.mapsTo` bundles `ContinuousOn.restrict_mapsTo` New functions: * `ContinuousMap.preimageValIncl : C(s ↓∩ t, t)` and `.inclPreimageVal C(s, t ↓∩ s)`, and their unbundled functions in `Set` * `Homeomorph.Set.preimageVal` witnesses that the two are opposite directions of a homeomorphism * Descending from a coherent set of subspaces is a quotient map The primary use for these bundled maps is easy composition and the ability to introduce them by rewriting right-to-left: it is much more convenient to write `subtypeVal.comp _` than to use either the anonymous constructor (which doesn't work in any position without an expected type) or `ContinuousMap.mk` (which will disappear as soon as it is coerced to a function, making it difficult to use in mixed-categorical contexts where many maps can only be reduced by introducing a composition with some other map.) This PR is part of a family of PRs that ultimately construct transformations in both directions between the concrete `Topology.RelCWComplex` and abstract `TopCat.RelativeCWComplex`. `.mapsTo` in particular bundles together a couple of potentially nontrivial proofs in a way that makes them easy to refer to later; I use it and `.subtypeVal` particularly heavily later in a dependent PR to build the cell inclusion maps on both sides of the equivalence. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) large-import 227/2 Mathlib/Data/Set/Subset.lean,Mathlib/Topology/Category/TopCat/Limits/Products.lean,Mathlib/Topology/Coherent.lean,Mathlib/Topology/Constructions.lean,Mathlib/Topology/Constructions/SumProd.lean,Mathlib/Topology/ContinuousMap/Basic.lean,scripts/noshake.json 7 15 ['adamtopaz', 'github-actions', 'mathlib4-merge-conflict-bot', 'robertmaxton42'] adamtopaz
assignee:adamtopaz
10-46500
10 days ago
10-46913
10 days ago
69-4016
69 days
33280 michelsol
author:michelsol
feat(MeasureTheory/Integral/IntervalIntegral): add variant `integral_deriv_eq_sub_uIoo` of 2nd theorem of calculus. Add a continuous on uIcc, differentiable on uIoo, deriv version of the 2nd fundamental theorem of calculus. This corresponds to what is written [here](https://en.wikipedia.org/wiki/Fundamental_theorem_of_calculus#Second_part). For example it makes it easier to compute the integral : ```lean4 ∫ x : ℝ in 0..1, (√(1 - x ^ 2))⁻¹ = ∫ x : ℝ in 0..1, deriv arcsin x = arcsin 1 - arcsin 0 ``` It is not possible to use [`interval_deriv_eq_sub`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/MeasureTheory/Integral/IntervalIntegral/FundThmCalculus.html#intervalIntegral.integral_deriv_eq_sub) which requires differentiability on all of [0,1], as `arcsin` isn't differentiable at 1. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability new-contributor 14/0 Mathlib/MeasureTheory/Integral/IntervalIntegral/FundThmCalculus.lean 1 1 ['github-actions'] EtienneC30
assignee:EtienneC30
10-43887
10 days ago
13-70512
13 days ago
13-70548
13 days
30391 rudynicolop
author:rudynicolop
feat(Data/List): list splitting definitions and lemmas This PR continues the work from #24395. Original PR: https://github.com/leanprover-community/mathlib4/pull/24395 new-contributor t-data 108/2 Mathlib/Data/List/Perm/Lattice.lean,Mathlib/Data/List/TakeDrop.lean 2 45 ['BoltonBailey', 'IlPreteRosso', 'TwoFX', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot', 'rudynicolop'] TwoFX
assignee:TwoFX
10-32805
10 days ago
19-50746
19 days ago
85-16073
85 days
30962 WangYiran01
author:WangYiran01
feat(Combinatorics/Enumerative): add lattice path lemmas and counts This PR adds definitions and theorems about monotone lattice paths: - Defines `pathCount`, `pathCountFrom`, `SubdiagProp`, and related structures. - Proves closed forms such as `pathCount_eq_closed`. - Adds Dyck/ballot subdiagonal property (`SubdiagProp`). All code builds successfully with `lake build`. t-combinatorics new-contributor 76/0 Mathlib.lean,Mathlib/Combinatorics/Enumerative/RecLatticePath.lean 2 3 ['github-actions', 'mathlib4-merge-conflict-bot'] awainverse
assignee:awainverse
10-9764
10 days ago
24-8899
24 days ago
44-8724
44 days
33339 Ruben-VandeVelde
author:Ruben-VandeVelde
feat: small lemmas about LeftInverse and image/preimage From sphere-eversion. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 9/1 Mathlib/Data/Set/Image.lean 1 3 ['Ruben-VandeVelde', 'github-actions', 'vihdzp'] nobody
10-6205
10 days ago
12-3230
12 days ago
12-3270
12 days
33064 DavidLedvinka
author:DavidLedvinka
feat(Probability): Add `condLExp`, conditional expectation with the Lebesgue integral Add definition of `condLExp`, conditional expectation using the Lebesgue integral. Also add basic API. t-measure-probability 275/0 Mathlib.lean,Mathlib/MeasureTheory/Function/ConditionalLExpectation.lean,Mathlib/MeasureTheory/Integral/Lebesgue/Add.lean,Mathlib/MeasureTheory/MeasurableSpace/CountablyGenerated.lean,Mathlib/MeasureTheory/MeasurableSpace/Defs.lean,Mathlib/MeasureTheory/Measure/AEMeasurable.lean 6 3 ['DavidLedvinka', 'github-actions', 'leanprover-radar'] EtienneC30
assignee:EtienneC30
9-49086
9 days ago
19-52110
19 days ago
20-53864
20 days
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. --- - [ ] depends on: #30436 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 324/1 Mathlib.lean,Mathlib/RingTheory/PowerSeries/Pentagonal.lean,Mathlib/Topology/Algebra/InfiniteSum/Pentagonal.lean,docs/1000.yaml 4 12 ['copilot-pull-request-reviewer', 'github-actions', 'mathlib4-dependent-issues-bot', 'vihdzp'] kex-y
assignee:kex-y
9-43905
9 days ago
12-64298
12 days ago
12-64756
12 days
33297 tb65536
author:tb65536
feat(Algebra/Polynomial/Roots): add `card_rootSet_le` This PR adds a lemma stating that `Set.ncard (p.rootSet B) ≤ p.natDegree` (we already have similar lemmas for `Polynomial.roots`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra large-import
label:t-algebra$
7/0 Mathlib/Algebra/Polynomial/Roots.lean 1 1 ['github-actions'] dagurtomas
assignee:dagurtomas
9-43904
9 days ago
13-39904
13 days ago
13-39878
13 days
33299 kingiler
author:kingiler
feat: Add decidable membership for Interval Implemented membership and corresponding decidable instance for `Interval`. Related [#mathlib4 > Proposal: Add decidable membership for Interval](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Proposal.3A.20Add.20decidable.20membership.20for.20Interval/with/565438009). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-order new-contributor 16/1 Mathlib/Order/Interval/Basic.lean 1 3 ['eric-wieser', 'github-actions', 'kingiler'] Vierkantor
assignee:Vierkantor
9-43903
9 days ago
13-27987
13 days ago
13-32569
13 days
33335 YaelDillies
author:YaelDillies
feat(Combinatorics/SimpleGraph): more about two-reachability --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 51/51 Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/EdgeConnectivity.lean,Mathlib/Combinatorics/SimpleGraph/DeleteEdges.lean 3 3 ['SnirBroshi', 'YaelDillies', 'github-actions'] nobody
9-14028
9 days ago
12-13010
12 days ago
12-13048
12 days
33084 joelriou
author:joelriou
feat(CategoryTheory): MorphismProperty induced on a quotient category Let `W : MorphismProperty C` and `homRel : HomRel C`. We assume that `homRel` is stable under pre- and postcomposition. We introduce a property `W.HasQuotient homRel` expressing that `W` induces a property of morphisms on the quotient category. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-category-theory maintainer-merge 181/79 Mathlib.lean,Mathlib/Algebra/Homology/HomotopyCategory.lean,Mathlib/CategoryTheory/Groupoid/FreeGroupoid.lean,Mathlib/CategoryTheory/MorphismProperty/Quotient.lean,Mathlib/CategoryTheory/PathCategory/Basic.lean,Mathlib/CategoryTheory/Quotient.lean,Mathlib/CategoryTheory/Quotient/Linear.lean,Mathlib/CategoryTheory/Quotient/Preadditive.lean 8 11 ['dagurtomas', 'github-actions', 'jcommelin', 'joelriou', 'robin-carlier'] joneugster
assignee:joneugster
8-43895
8 days ago
12-15489
12 days ago
18-68360
18 days
32744 NoneMore
author:NoneMore
feat(ModelTheory/Definablity): add `DefinableFun` definition and lemmas This PR adds two basic shapes of definable sets and `DefinableFun` definition with relevant lemmas. The main result is `Set.Definable.preimage_of_map` asserting that the preimage of a definable set under a definable map is definable. There are also some tool lemmas derived by the preimage lemma. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic new-contributor 151/0 Mathlib/ModelTheory/Definability.lean 1 58 ['NoneMore', 'github-actions', 'staroperator'] fpvandoorn
assignee:fpvandoorn
6-75211
6 days ago
27-28561
27 days ago
27-73864
27 days
33465 SnirBroshi
author:SnirBroshi
chore(Data/Finset/Insert): golf `eq_singleton_iff_nonempty_unique_mem` using grind --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 1/8 Mathlib/Data/Finset/Insert.lean 1 1 ['github-actions'] nobody
6-67530
6 days ago
6-67537
6 days ago
6-67571
6 days
32803 erdOne
author:erdOne
feat(RIngTheory): more-linear version of `tensorKaehlerEquiv` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 83/7 Mathlib/RingTheory/Kaehler/TensorProduct.lean 1 16 ['Ruben-VandeVelde', 'erdOne', 'github-actions', 'mattrobball', 'robin-carlier'] mattrobball
assignee:mattrobball
6-52205
6 days ago
6-52205
6 days ago
16-34888
16 days
33278 harahu
author:harahu
doc(MeasureTheory): remove stale paragraph - Remove a paragraph describing definition of notation that does not happen in this file. - Also align a scalar multiplication symbol in the docs with the symbol used in the code. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability 1/4 Mathlib/MeasureTheory/Integral/Bochner/L1.lean 1 4 ['bryangingechen', 'github-actions', 'harahu', 'mathlib4-merge-conflict-bot'] kex-y
assignee:kex-y
6-46676
6 days ago
7-46478
7 days ago
14-3785
14 days
31325 joelriou
author:joelriou
feat(AlgebraicTopology): a computable monoidal functor instance for `hoFunctor` We construct a computable equivalence of categories `(X ⊗ Y).HomotopyCategory ≌ X.HomotopyCategory × Y.HomotopyCategory` for `2`-truncated simplicial sets `X` and `Y`. This allows to make the bicategory instance on quasicategories computable. --- - [x] depends on: #33201 - [x] depends on: #31174 - [x] depends on: #31250 - [x] depends on: #31254 - [x] depends on: #31274 - [x] depends on: #31265 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebraic-topology 298/28 Mathlib/AlgebraicTopology/Quasicategory/StrictBicategory.lean,Mathlib/AlgebraicTopology/SimplicialSet/HoFunctorMonoidal.lean,Mathlib/AlgebraicTopology/SimplicialSet/NerveAdjunction.lean 3 16 ['github-actions', 'joelriou', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'robin-carlier'] robin-carlier
assignee:robin-carlier
6-12265
6 days ago
6-12265
6 days ago
12-60796
12 days
33291 BoltonBailey
author:BoltonBailey
refactor(Computability): File for state transition systems This PR makes a new file to contain content having to do with state transition systems defined by a function `σ → Option σ`. This content was previously split over `PostTuringMachine.lean` and `TMComputable.lean`, but since these definitions don't only apply to Turing machines in particular, it seems sensible to refactor them and remove them from the `Turing` namespace and put them in a new `StateTransition` namespace. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-computability 320/233 Mathlib.lean,Mathlib/Computability/PostTuringMachine.lean,Mathlib/Computability/StateTransition.lean,Mathlib/Computability/TMConfig.lean,Mathlib/Computability/TMToPartrec.lean,Mathlib/Computability/TuringMachine.lean 6 1 ['github-actions'] nobody
5-59241
5 days ago
13-53488
13 days ago
13-53534
13 days
33409 jsm28
author:jsm28
feat(LinearAlgebra/AffineSpace/Ceva): Ceva's theorem Add Ceva's theorem. Unlike various previous attempts, I think this in appropriate generality for mathlib; it starts with a version for an arbitary (possibly infinite) affinely independent family of points (not necessarily spanning the whole space), in any affine space over any ring, and with the second point given on each line not necessarily being on the opposite face, then deduces a simpler version for a finite family, then deduces versions for a triangle, now with actual cevians (lines between a vertex and a point on the opposite side), either just multiplying weights (here the ring requires no zero divisors) or expressed with a product of divisions equal to 1 (here it becomes a field). This doesn't include any form of the converse (with a "concurrent or parallel" conclusion, and note that you don't need affine independence for the converse), or variants of the forward direction where you're given parallel lines rather than concurrent lines, but I think those things can reasonably be done in followups. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
243/0 Mathlib.lean,Mathlib/LinearAlgebra/AffineSpace/AffineSubspace/Basic.lean,Mathlib/LinearAlgebra/AffineSpace/Ceva.lean,docs/100.yaml,docs/1000.yaml 5 9 ['github-actions', 'jsm28', 'plby'] mariainesdff
assignee:mariainesdff
5-43916
5 days ago
8-53998
8 days ago
8-53972
8 days
30758 Timeroot
author:Timeroot
chore: tag abs_inv and abs_div with grind= --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
2/1 Mathlib/Algebra/Order/Field/Basic.lean 1 n/a ['github-actions'] nobody
78-60241
2 months ago
unknown
unknown
33481 NoneMore
author:NoneMore
feat(ModelTheory/Encoding): add `Countable` instances for (bounded) formulas in countable languages Prepare for the OTT proof. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic new-contributor 27/0 Mathlib/ModelTheory/Encoding.lean 1 1 ['github-actions'] nobody
5-27659
5 days ago
6-10077
6 days ago
6-10112
6 days
31121 jessealama
author:jessealama
feat: add ComplexShape.EulerCharSigns for generalized Euler characteristic Add `ComplexShape.EulerCharSigns` typeclass providing the alternating signs `χ : ι → ℤˣ` for Euler characteristic computations. Instances are provided for `up ℕ`, `down ℕ`, `up ℤ`, and `down ℤ`. The Euler characteristic definitions (`eulerChar` and `eulerCharTsum`) are defined on `GradedObject` with `ComplexShape` as an explicit parameter. The `HomologicalComplex` versions are abbreviations that apply these to `C.X` and `C.homology`. Both finite and infinite sum versions are provided. Split from #29713 as suggested by @joelriou. t-category-theory t-algebra
label:t-algebra$
188/0 Mathlib.lean,Mathlib/Algebra/Homology/EulerCharacteristic.lean 2 10 ['github-actions', 'jessealama', 'joelriou', 'mathlib4-merge-conflict-bot'] mattrobball
assignee:mattrobball
5-20539
5 days ago
12-19109
12 days ago
27-39596
27 days
32438 JovanGerb
author:JovanGerb
feat: unfold-boundaries in `to_dual` This PR introduces a new feature to `to_dual` that allows us to have definitions whose dual is not definitionally equal to the dual of the value. This is crucial for many definitions that are dual to something morally but not definitionally. For example, `DecidableLE`, `Set.Ioo`, `Set.Ico`, `CovBy` , `Monotone`. - [x] Tracing to see what this is doing - [x] Improve the UI of applying the `to_dual_insert_cast` and `to_dual_insert_cast_fun` attributes. - [x] Add tests - [x] Better documentation --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta 518/128 Mathlib.lean,Mathlib/Combinatorics/Quiver/Basic.lean,Mathlib/Order/Basic.lean,Mathlib/Order/Cover.lean,Mathlib/Order/Defs/LinearOrder.lean,Mathlib/Order/Defs/PartialOrder.lean,Mathlib/Order/GaloisConnection/Defs.lean,Mathlib/Order/Interval/Set/Defs.lean,Mathlib/Order/Monotone/Defs.lean,Mathlib/Order/WithBot.lean,Mathlib/Tactic.lean,Mathlib/Tactic/ToDual.lean,Mathlib/Tactic/Translate/Core.lean,Mathlib/Tactic/Translate/ToDual.lean,Mathlib/Tactic/Translate/UnfoldBoundary.lean,MathlibTest/ToDual.lean 16 12 ['JovanGerb', 'fpvandoorn', 'github-actions', 'leanprover-radar', 'mathlib4-merge-conflict-bot', 'vihdzp'] bryangingechen
assignee:bryangingechen
5-14708
5 days ago
5-14733
5 days ago
15-31039
15 days
32654 YaelDillies
author:YaelDillies
feat(Combinatorics): a clique has size at most the chromatic number There already exists a version of this lemma for cliques given by a set, but it's impractical to provide an explicit clique on an explicit graph as a set, rather than an indexed family, especially because computing the size of the set would then involve proving that it is the range of an injective function, even though being a clique already implies being injective! Application: google-deepmind/formal-conjectures#1369 Also rename `coloringOfIsEmpty` and `colorable_of_isEmpty` to leverage anonymous dot notation, and make more arguments implicit. From FormalConjectures --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 51/40 Mathlib/Combinatorics/SimpleGraph/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Coloring.lean 2 20 ['SnirBroshi', 'YaelDillies', 'github-actions'] b-mehta
assignee:b-mehta
5-9350
5 days ago
29-70973
29 days ago
29-71004
29 days
33520 NoneMore
author:NoneMore
feat(ModelTheory/ElementarySubstructures): add a variant of Tarski-Vaught test taking sets as input There should exist an `ElementarySubstructure.copy` such that we can directly bundle the set itself instaed of its closure as an elementary substructure. The other direction depends on #33458. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic new-contributor 63/0 Mathlib/ModelTheory/ElementarySubstructures.lean 1 1 ['github-actions'] nobody
4-81098
4 days ago
5-6995
5 days ago
5-7028
5 days
33523 jsm28
author:jsm28
feat(Combinatorics/Tiling/Tile): tiles and protosets for tilings Start setting up definitions for tilings in a discrete context with definitions of tiles and protosets (indexed families of tiles, predicates meaning such a family is a tiling, and various other properties of such families, are to follow in subsequent PRs). The module doc string discusses some of the overall design and different definitions that appear in the literature (not strictly limited to the concepts defined in this one file). Here are some overall design choices from a mathlib perspective: * The discrete and continuous theories are to be developed separately rather than attempting to have a single set of definitions and lemmas that works in both places, so that topological concepts don't need to be involved when working in a discrete context. While some very basic API lemmas might work with analogous proofs for both versions (and the API for continuous tilings *should* follow the lemmas and lemma naming for the discrete case where that makes sense), they would rapidly diverge as soon as even slight mathematical content is involved. For example, in the discrete case, relating weak and strong periodicity typically follows from straightforward properties of the group action, whereas for isometries in Euclidean n-space it needs Bieberbach's first theorem on space groups to show that strongly periodic tilings are also weakly n-periodic. * The discrete theory is here placed in `Mathlib.Combinatorics.Tiling`, and in a namespace `Discrete`, with the expectation that the continuous theory might them go in `Mathlib.Combinatorics.Tiling.Continuous` with corresponding definitions in a namespace `Continuous` (though other names could be used if preferred). * The theory is set up in the context of a multiplicative group action (which of course includes but is more general than the case of a group acting on itself). The expectation is that if it's desired to apply it in future with additive group actions, then `to_additive` would be used to set up a corresponding additive version of the theory. * As discussed in the module doc string, markings on tiles are handled by the combination of defining a protoset as an indexed family (not a set) of prototiles so that otherwise identical prototiles can be distinguished, and each prototile coming with a subgroup of its stablizer so that tiles can be considered to have asymmetrical markings when required. Matching rules are to be handled as predicates on what tilings are considered valid in a given context (together with predicates on those predicates so that results can be stated, for example, as applying with any tiling predicate that only looks at local properties of bounded regions of the tiling). Zulip discussion: https://leanprover.zulipchat.com/#narrow/channel/116395-maths/topic/Discussion.20-.20Definition.20of.20tilings From AperiodicMonotilesLean. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 311/0 Mathlib.lean,Mathlib/Combinatorics/Tiling/Tile.lean,docs/references.bib 3 15 ['Ruben-VandeVelde', 'github-actions', 'jsm28'] nobody
4-73817
4 days ago
4-76396
4 days ago
4-76370
4 days
33527 SnirBroshi
author:SnirBroshi
feat(Combinatorics/SimpleGraph/Connectivity/Subgraph): `w.toSubgraph ≤ G' ↔ w.edgeSet ⊆ G'.edgeSet` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 9/1 Mathlib/Combinatorics/SimpleGraph/Connectivity/Subgraph.lean 1 1 ['github-actions'] nobody
4-60492
4 days ago
4-60501
4 days ago
4-60534
4 days
31595 astrainfinita
author:astrainfinita
chore: redefine `Ideal.IsPrime` Redefine `Ideal.IsPrime` to make it correct for non-commutative cases --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
330/100 Mathlib/Algebra/Order/Ring/Ordering/Defs.lean,Mathlib/AlgebraicGeometry/StructureSheaf.lean,Mathlib/RingTheory/DedekindDomain/Ideal/Lemmas.lean,Mathlib/RingTheory/GradedAlgebra/Radical.lean,Mathlib/RingTheory/Ideal/AssociatedPrime/Basic.lean,Mathlib/RingTheory/Ideal/IsPrimary.lean,Mathlib/RingTheory/Ideal/Maps.lean,Mathlib/RingTheory/Ideal/Maximal.lean,Mathlib/RingTheory/Ideal/Oka.lean,Mathlib/RingTheory/Ideal/Operations.lean,Mathlib/RingTheory/Ideal/Over.lean,Mathlib/RingTheory/Ideal/Pointwise.lean,Mathlib/RingTheory/Ideal/Prime.lean,Mathlib/RingTheory/Ideal/Prod.lean,Mathlib/RingTheory/Ideal/Quotient/Basic.lean,Mathlib/RingTheory/Ideal/Quotient/Operations.lean,Mathlib/RingTheory/Localization/AtPrime/Basic.lean,Mathlib/RingTheory/Localization/Ideal.lean,Mathlib/RingTheory/Polynomial/Basic.lean,Mathlib/RingTheory/PrincipalIdealDomain.lean,Mathlib/RingTheory/Spectrum/Prime/Topology.lean,Mathlib/RingTheory/Valuation/Basic.lean 22 29 ['alreadydone', 'artie2000', 'astrainfinita', 'erdOne', 'github-actions', 'leanprover-bot', 'leanprover-community-mathlib4-bot', 'mathlib4-merge-conflict-bot'] alreadydone
assignee:alreadydone
4-59069
4 days ago
9-41749
9 days ago
26-33890
26 days
33025 JovanGerb
author:JovanGerb
feat(gcongr): beef up `@[gcongr]` tag to accept `↔` & any argument order This PR modifies the `@[gcongr]` tag to accept lemmas in more forms. - Iff lemmas are now accepted, and are turned into an auxiliary lemmas that is simply one of the two implications. - Implicational gcongr lemmas now don't need to have their arguments given in the "correct" order. An auxiliary lemma is generated if necessary. The auxiliary lemma generation is done analogously to `simp` which creates little lemmas `Foo._simp_1`., I also went throught all lemmas that have `GCongr.` in the name, and removed all but one of them (the remaining one is `GCongr.mem_of_le_of_mem`) A future PR may introduce the `gcongr at` tactic, which does `gcongr` but at hypotheses. This would be using the reverse direction of the iff lemmas tagged with `gcongr`. For this reason it is preferred to tag the iff lemma if possible. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta 206/276 Mathlib/Algebra/Module/Submodule/Basic.lean,Mathlib/Algebra/Order/BigOperators/Expect.lean,Mathlib/Algebra/Order/Pi.lean,Mathlib/Algebra/Order/Ring/Cast.lean,Mathlib/Algebra/Order/Ring/Ordering/Basic.lean,Mathlib/Analysis/SpecialFunctions/Arsinh.lean,Mathlib/Data/Finset/Defs.lean,Mathlib/Data/Finset/Image.lean,Mathlib/Data/Finset/Range.lean,Mathlib/Data/Finsupp/Order.lean,Mathlib/Data/Int/Basic.lean,Mathlib/Data/NNReal/Defs.lean,Mathlib/Data/Set/Insert.lean,Mathlib/Data/SetLike/Basic.lean,Mathlib/MeasureTheory/Function/SimpleFunc.lean,Mathlib/NumberTheory/LucasLehmer.lean,Mathlib/Order/Basic.lean,Mathlib/Order/Filter/Basic.lean,Mathlib/Order/Fin/Basic.lean,Mathlib/Order/Hom/Basic.lean,Mathlib/Order/Hom/Lattice.lean,Mathlib/Order/Interval/Finset/Basic.lean,Mathlib/Order/Interval/Set/Basic.lean,Mathlib/Order/Nucleus.lean,Mathlib/Order/Sublocale.lean,Mathlib/RingTheory/FractionalIdeal/Basic.lean,Mathlib/SetTheory/ZFC/VonNeumann.lean,Mathlib/Tactic/GCongr/Core.lean,MathlibTest/GCongr/GCongr.lean 29 3 ['github-actions', 'mathlib4-merge-conflict-bot'] dwrensha
assignee:dwrensha
4-43888
4 days ago
19-39496
19 days ago
20-82908
20 days
33221 stepan2698-cpu
author:stepan2698-cpu
feat: definition of an intertwining map Adds the definition of an intertwining map of representations, with an instance of an A-module structure. Proves that a multiplication by a central element is an intertwining map. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra new-contributor
label:t-algebra$
355/11 Mathlib.lean,Mathlib/RepresentationTheory/Intertwining.lean,Mathlib/RepresentationTheory/Irreducible.lean,Mathlib/RepresentationTheory/Subrepresentation.lean 4 1 ['github-actions'] ocfnash
assignee:ocfnash
4-43887
4 days ago
16-31297
16 days ago
16-31337
16 days
33397 themathqueen
author:themathqueen
feat(Topology/Algebra/Star/LinearMap): intrinsic star for continuous linear maps --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology t-algebra
label:t-algebra$
100/0 Mathlib.lean,Mathlib/Topology/Algebra/Star/LinearMap.lean 2 2 ['github-actions', 'j-loreaux'] ocfnash
assignee:ocfnash
4-43887
4 days ago
7-61298
7 days ago
9-33457
9 days
33416 vihdzp
author:vihdzp
chore(Order/GameAdd): add `elab_as_elim` attributes This PR does three things: - Rename `GameAdd.fix` to the more illustrative `GameAdd.recursion` - Add `elab_as_elim` attributes on `GameAdd.recursion` - Deprecate the duplicate `GameAdd.induction` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-order 24/14 Mathlib/Order/GameAdd.lean,Mathlib/SetTheory/PGame/Order.lean,Mathlib/SetTheory/ZFC/Ordinal.lean 3 1 ['github-actions'] Vierkantor
assignee:Vierkantor
4-43883
4 days ago
8-41027
8 days ago
8-41008
8 days
33443 sahanwijetunga
author:sahanwijetunga
feat: Define Isometries of Bilinear Spaces --- We define Isometries of Bilinear Spaces, closely following the implementation of isometries of quadratic spaces. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra new-contributor
label:t-algebra$
275/0 Mathlib.lean,Mathlib/LinearAlgebra/BilinearForm/Isometry.lean,Mathlib/LinearAlgebra/BilinearForm/IsometryEquiv.lean 3 1 ['github-actions'] dagurtomas
assignee:dagurtomas
4-43881
4 days ago
7-52544
7 days ago
7-52582
7 days
33118 thomaskwaring
author:thomaskwaring
feat(Combinatorics/SimpleGraph/Acyclic): every graph has a spanning forest. We show that every graph has a spanning forest: defined to be an acyclic subgraph with the same reachability relation as the larger graph. As a special case, every connected graph has a spanning tree. --- Each of these results (spanning forest & spanning tree) are proved in two versions: a general case where the forest / tree is found by extending a given acyclic subgraph, and the special case where that subgraph is empty. - [ ] depends on: #32043 t-combinatorics new-contributor 29/5 Mathlib/Combinatorics/SimpleGraph/Acyclic.lean 1 6 ['SnirBroshi', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'thomaskwaring', 'vlad902'] nobody
4-41436
4 days ago
5-31087
5 days ago
5-34275
5 days
33538 JohnnyTeutonic
author:JohnnyTeutonic
feat(Data/Matrix/Cartan): non-simply-laced theorems for F and G B/C are left for follow-up --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 17/0 Mathlib/Data/Matrix/Cartan.lean 1 1 ['github-actions'] nobody
4-22706
4 days ago
4-22946
4 days ago
4-22980
4 days
33475 BoltonBailey
author:BoltonBailey
feat(Logic/IsEmpty): add theorems relating surjectivity and emptiness In particular, this adds a lemma saying that with an empty domain, a function is surjective iff its range is empty, and various forms of this. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic 11/2 Mathlib/Logic/IsEmpty.lean 1 13 ['BoltonBailey', 'SnirBroshi', 'eric-wieser', 'github-actions'] nobody
4-15860
4 days ago
5-55994
5 days ago
6-38562
6 days
27706 xroblot
author:xroblot
feat(RingTheory/Localization/AtPrime): inertia degree and ramification index are preserved by localization Let `R ⊆ S` be an extension of rings and `p` be a prime ideal of `R`. Denote by `Rₚ` the localization of `R` at the complement of `p` and by `Sₚ` the localization of `S` at the (image) of the complement of `p`. In this PR, we prove that the bijection between the (nonzero) prime ideals of `Sₚ` and the prime ideals of `S` above `p` preserves the residual degree and the ramification index. --- - [x] depends on: #27794 - [x] depends on: #27796 - [x] depends on: #27798 - [x] depends on: #28526 - [x] depends on: #29322 - [x] depends on: #32045 large-import t-ring-theory 192/9 Mathlib/NumberTheory/RamificationInertia/Basic.lean,Mathlib/RingTheory/Localization/AtPrime/Basic.lean,Mathlib/RingTheory/Localization/AtPrime/Extension.lean 3 9 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'riccardobrasca', 'xroblot'] riccardobrasca
assignee:riccardobrasca
3-84541
3 days ago
3-84541
3 days ago
4-1178
4 days
33551 metakunt
author:metakunt
feat(Data/Nat/Factorization/PrimePow): Add Nat.primeFactors_nontrivial_of_two_le_of_not_isPrimePow t-data 11/0 Mathlib/Data/Nat/Factorization/PrimePow.lean 1 1 ['github-actions'] nobody
3-77248
3 days ago
3-77248
3 days ago
3-77292
3 days
33435 astrainfinita
author:astrainfinita
feat: algebra automorphisms of monoid algebras --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
53/3 Mathlib/Algebra/MonoidAlgebra/Basic.lean 1 1 ['github-actions'] kbuzzard
assignee:kbuzzard
3-58181
3 days ago
7-79941
7 days ago
7-79925
7 days
32886 alreadydone
author:alreadydone
refactor(Algebra/Order): change `MulArchimedeanClass.subgroup` to `FiniteArchimedeanClass.subgroup` This gets rid of a junk value without much modification the main HahnEmbedding application. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra t-order
label:t-algebra$
298/157 Mathlib/Algebra/Order/Archimedean/Class.lean,Mathlib/Algebra/Order/Module/Archimedean.lean,Mathlib/Algebra/Order/Module/HahnEmbedding.lean 3 7 ['alreadydone', 'github-actions', 'vihdzp', 'wwylele'] Vierkantor
assignee:Vierkantor
3-56305
3 days ago
24-36692
24 days ago
24-36667
24 days
30981 jsm28
author:jsm28
feat(Geometry/Euclidean/Angle/Bisector): oriented angle bisection mod π Add lemmas relating equal distance to two lines to bisecting the angle between them mod π (expressed as usual as equality of twice angles), building on the previous lemmas (#30477) dealing with bisection mod 2π. --- - [ ] depends on: #30474 - [ ] depends on: #30477 - [ ] depends on: #30600 - [ ] depends on: #30703 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-euclidean-geometry 193/50 Mathlib/Geometry/Euclidean/Angle/Bisector.lean 1 12 ['JovanGerb', 'github-actions', 'jsm28', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] JovanGerb
assignee:JovanGerb
16-72656
16 days ago
50-8470
1 month ago
54-51697
54 days
33467 euprunin
author:euprunin
chore: golf using `grind`. add `grind` annotations. --- The goal of this golfing PR is to decrease the number of times lemmas are called explicitly (replacing calls to lemmas with calls to tactics). Any decrease in compilation time is a welcome side effect, although it is not a primary objective. Trace profiling results (shown if ≥10 ms before or after): * `CategoryTheory.Limits.Pi.ι_π`: <10 ms before, 40 ms after * `CategoryTheory.Limits.Sigma.ι_π`: <10 ms before, 39 ms after * `Stream'.Seq.head_eq_none_iff`: <10 ms before, 87 ms after * `Part.mem_ωSup`: 37 ms before, <10 ms after 🎉 This golfing PR is batched under the following guidelines: * Up to ~5 changed files per PR * Up to ~25 changed declarations per PR * Up to ~100 changed lines per PR --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 10/24 Mathlib/CategoryTheory/EqToHom.lean,Mathlib/CategoryTheory/Limits/Shapes/ZeroMorphisms.lean,Mathlib/Data/Seq/Defs.lean,Mathlib/Order/OmegaCompletePartialOrder.lean 4 3 ['euprunin', 'github-actions', 'leanprover-radar'] alexjbest
assignee:alexjbest
3-43878
3 days ago
6-53527
6 days ago
6-53500
6 days
33470 erdOne
author:erdOne
feat: generalize `Polynomial.freeMonic` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 80/52 Mathlib.lean,Mathlib/Algebra/Polynomial/FreeMonic.lean,Mathlib/RingTheory/Polynomial/UniversalFactorizationRing.lean 3 1 ['github-actions'] thorimur
assignee:thorimur
3-43877
3 days ago
6-53128
6 days ago
6-53101
6 days
33469 erdOne
author:erdOne
feat(LinearAlgebra): make TensorProduct.finsuppLeft and friends heterobasic --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 77/137 Mathlib/LinearAlgebra/DirectSum/Finsupp.lean,Mathlib/LinearAlgebra/DirectSum/TensorProduct.lean,Mathlib/LinearAlgebra/TensorProduct/Basis.lean,Mathlib/LinearAlgebra/TensorProduct/Submodule.lean,Mathlib/RepresentationTheory/Coinvariants.lean,Mathlib/RepresentationTheory/Rep.lean,Mathlib/RingTheory/Flat/FaithfullyFlat/Basic.lean,Mathlib/RingTheory/Ideal/Quotient/Index.lean,Mathlib/RingTheory/LocalRing/Module.lean,Mathlib/RingTheory/Localization/BaseChange.lean,Mathlib/RingTheory/PicardGroup.lean,Mathlib/RingTheory/TensorProduct/IsBaseChangeFree.lean,Mathlib/RingTheory/TensorProduct/MvPolynomial.lean 13 1 ['github-actions'] mariainesdff
assignee:mariainesdff
3-43877
3 days ago
6-53183
6 days ago
6-53156
6 days
29235 yoh-tanimoto
author:yoh-tanimoto
feat(Topology/Algebra/Module/ClosedSubmodule): add `mapEquiv`, a variation of `ClosedSubmodule.map` for CLE add `ClosedSubmodule.mapEquiv` for continuous linear equivalence. In this case, a closed submodule is mapped to a closed submodule, so the definitions are easier and behave nicely with `closure` and `⊔`. motivation: needed to define standard subspaces in a Hilbert space (scalar multiplication by `Complex.I`) #29251 https://ems.press/content/serial-article-files/48171 - [x] depends on: #29230 for `Lattice` `CompleteLattice` t-topology 76/1 Mathlib/Topology/Algebra/Module/ClosedSubmodule.lean 1 3 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] fpvandoorn
assignee:fpvandoorn
3-36758
3 days ago
3-42235
3 days ago
71-12812
71 days
33582 urkud
author:urkud
feat(ContDiffHolder/Moreira): define $C^{k+(α)}$ maps From https://github.com/urkud/SardMoreira --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis 288/0 Mathlib.lean,Mathlib/Analysis/Calculus/ContDiffHolder/Moreira.lean,Mathlib/Analysis/SpecialFunctions/Pow/Asymptotics.lean,docs/references.bib 4 1 ['github-actions'] nobody
3-34001
3 days ago
3-34038
3 days ago
3-34080
3 days
25841 mitchell-horner
author:mitchell-horner
feat(Combinatorics/SimpleGraph): prove the Kővári–Sós–Turán theorem Prove the Kővári–Sós–Turán theorem (an upper bound on the Zarankiewicz function) --- - [x] depends on: #19865 - [x] depends on: #20738 - [x] depends on: #27602 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) --- *This PR continues the work from #20240.* *Original PR: https://github.com/leanprover-community/mathlib4/pull/20240* t-combinatorics 484/0 Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Combinatorics/SimpleGraph/Extremal/KovariSosTuran.lean,Mathlib/Combinatorics/SimpleGraph/Extremal/Zarankiewicz.lean,Mathlib/Combinatorics/SimpleGraph/Maps.lean,docs/1000.yaml 6 11 ['SnirBroshi', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'mitchell-horner'] nobody
3-23707
3 days ago
3-23761
3 days ago
48-39153
48 days
33039 euprunin
author:euprunin
chore(Data/List): deprecate `ext_get_iff` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 1/7 Mathlib/Data/List/Basic.lean 1 5 ['euprunin', 'github-actions', 'jcommelin'] pechersky
assignee:pechersky
3-9372
3 days ago
13-54608
13 days ago
14-35975
14 days
33589 JovanGerb
author:JovanGerb
chore(Lean/Meta/RefinedDiscrTree/Basic): remove `privateInPublic` This PR fixes cases of `privateInPublic` in the `RefinedDiscrTree` code. The offending pattern is that an instance is defined using a private definition. The solution is to not mark that definition as private. Also avoid a use of `nonrec` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta 13/24 Mathlib/Lean/Meta/RefinedDiscrTree/Basic.lean 1 1 ['github-actions'] nobody
3-2121
3 days ago
3-14613
3 days ago
3-14650
3 days
33594 smmercuri
author:smmercuri
feat: `HeightOneSpectrum.valuation` is rank one for number fields - If `K` is a number field and `v` is a height-one prime ideal then `v.valuation K` is rank one. - In general, if `v` is a rank one valuation of `K`, then its extension to the `v`-adic completion `v.Completion` is also rank one, provided in `Valuation.instRankOneCompletion` - Together these refactor and deprecate `instRankOneValuedAdicCompletion`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) large-import 18/8 Mathlib/NumberTheory/NumberField/FinitePlaces.lean,Mathlib/RingTheory/Valuation/RankOne.lean 2 2 ['github-actions', 'smmercuri'] nobody
2-82673
2 days ago
2-86321
2 days ago
2-86323
2 days
33599 nielstron
author:nielstron
feat(Computability/ContextFreeGrammar): closure under union --- This PR picks up https://github.com/leanprover-community/mathlib4/pull/13514 and resolves the outstanding errors. - [ ] depends on #33592 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-computability 506/0 Mathlib/Computability/ContextFreeGrammar.lean 1 1 ['github-actions'] nobody
2-77777
2 days ago
3-1838
3 days ago
3-1879
3 days
33607 xgenereux
author:xgenereux
feat: primeSpectrum_eq_of_KrullDimLEOne Given a local ring `R` which is also a domain with `Ring.KrullDimLE 1 R` (or equivalently `Ring.DimensionLEOne`) a prime is either `⊥` or`⊤`. The application I have in mind is `IsDiscreteValuationRing R`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 13/0 Mathlib/RingTheory/Spectrum/Prime/Topology.lean 1 1 ['github-actions'] nobody
2-73307
2 days ago
2-73307
2 days ago
2-73352
2 days
33403 xroblot
author:xroblot
feat(GroupTheory/FiniteAbelian): prove that the restriction map is surjective Let `G` be a finite commutative group and let `H` be a subgroup. If `M` is a commutative monoid such that `G →* Mˣ` and `H →* Mˣ` are both finite (this is the case for example if `M` is a commutative domain), then any homomorphism `H →* Mˣ` can be extended to an homomorphism `G →* Mˣ`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 89/13 Mathlib/Algebra/Group/Submonoid/Operations.lean,Mathlib/GroupTheory/Exponent.lean,Mathlib/GroupTheory/FiniteAbelian/Duality.lean,Mathlib/GroupTheory/QuotientGroup/Basic.lean,Mathlib/NumberTheory/MulChar/Duality.lean,Mathlib/RingTheory/RootsOfUnity/Basic.lean 6 7 ['Ruben-VandeVelde', 'github-actions', 'xroblot'] urkud
assignee:urkud
2-73092
2 days ago
9-4574
9 days ago
9-4547
9 days
32812 harahu
author:harahu
doc(Geometry): fix typos Typos found and fixed by Codex. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 17/17 Mathlib/Geometry/Euclidean/MongePoint.lean,Mathlib/Geometry/Manifold/Bordism.lean,Mathlib/Geometry/Manifold/Immersion.lean,Mathlib/Geometry/Manifold/MFDeriv/Defs.lean,Mathlib/Geometry/Manifold/PartitionOfUnity.lean,Mathlib/Geometry/Manifold/Riemannian/Basic.lean,Mathlib/Geometry/Manifold/VectorBundle/Hom.lean,Mathlib/Geometry/RingedSpace/PresheafedSpace/Gluing.lean 8 3 ['github-actions', 'mathlib4-merge-conflict-bot'] nobody
2-72356
2 days ago
2-72390
2 days ago
24-1446
24 days
33588 JovanGerb
author:JovanGerb
chore(Geometry/Euclidean/SignedDist): remove `privateInPublic` When I originally PRed `signedDistLinear`, I wasn't sure whether it should be marked `private`. It seems now that it should not have been private, because this violates `privateInPublic`. This PR fixes that. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-euclidean-geometry 4/14 Mathlib/Geometry/Euclidean/SignedDist.lean 1 3 ['JovanGerb', 'github-actions', 'vihdzp'] nobody
2-67392
2 days ago
3-15513
3 days ago
3-15549
3 days
33490 YaelDillies
author:YaelDillies
refactor(Data/Finsupp): remove `DecidableEq` argument from `curry` This is motivated by it spuriously requiring extra decidability assumptions in group cohomology. This partially reverts #24746. No motivation was given there for why computability was necessary. `Finsupp.curry` will be made computable again anyway once `Finsupp` is redefined to be `DFinsupp`. From ClassFieldTheory --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data CFT 15/21 Mathlib/Data/Finsupp/Basic.lean,Mathlib/LinearAlgebra/Finsupp/Defs.lean,Mathlib/LinearAlgebra/Finsupp/LinearCombination.lean,Mathlib/RepresentationTheory/Homological/GroupCohomology/Basic.lean,Mathlib/RepresentationTheory/Homological/GroupCohomology/FiniteCyclic.lean,Mathlib/RepresentationTheory/Homological/GroupCohomology/Shapiro.lean,Mathlib/RepresentationTheory/Homological/Resolution.lean,Mathlib/RepresentationTheory/Rep.lean,Mathlib/RingTheory/AlgebraTower.lean 9 5 ['YaelDillies', 'eric-wieser', 'github-actions', 'tb65536'] nobody
2-62651
2 days ago
5-64521
5 days ago
5-64496
5 days
33609 xgenereux
author:xgenereux
refactor: Ideal.bot_prime as an instance --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 14/18 Mathlib/Algebra/Order/Ring/Ordering/Basic.lean,Mathlib/RingTheory/DedekindDomain/Ideal/Lemmas.lean,Mathlib/RingTheory/Ideal/GoingUp.lean,Mathlib/RingTheory/Ideal/Maps.lean,Mathlib/RingTheory/Ideal/Maximal.lean,Mathlib/RingTheory/Ideal/MinimalPrime/Basic.lean,Mathlib/RingTheory/Ideal/NatInt.lean,Mathlib/RingTheory/Ideal/Prime.lean,Mathlib/RingTheory/Jacobson/Ring.lean,Mathlib/RingTheory/KrullDimension/Basic.lean,Mathlib/RingTheory/KrullDimension/Zero.lean,Mathlib/RingTheory/LocalRing/ResidueField/Fiber.lean,Mathlib/RingTheory/Localization/Ideal.lean,Mathlib/RingTheory/Spectrum/Prime/Basic.lean,Mathlib/RingTheory/Spectrum/Prime/Topology.lean 15 5 ['github-actions', 'leanprover-radar', 'vihdzp', 'xgenereux'] nobody
2-61897
2 days ago
2-61955
2 days ago
2-61936
2 days
33100 themathqueen
author:themathqueen
refactor(Algebra/Order/Field/Basic): generalize file from `LinearOrder` to `PartialOrder` and `PosMulReflectLT` It's a well-known easy fact that there is no way to equip `ℂ` with a *linear* order satisfying `IsStrictOrderedRing`. However, it is equipped with a partial order (available in the `ComplexOrder` namespace) given by `a ≤ b ↔ a.re ≤ b.re ∧ a.im = b.im`. This order satisfies `IsStrictOrderedRing`. However, it has some other nice properties, for instance `0 < a⁻¹ ↔ 0 < a` (because it is a `GroupWithZero` satisfying `PosMulReflectLT` so `inv_pos` applies), and moreover, in this PR we also show that a (partially) ordered field with this property satisfies `a⁻¹ < 0 ↔ a < 0`. This means that the field operation is well-behaved in regards to elements comparable with zero. This PR refactors `Algebra/Order/Field/Basic.lean` so that it applies to *partially* ordered fields that in addition satisfy `PosMulReflectLT` (e.g., `ℂ`). The vast majority of the lemmas are applicable in this more general setting, albeit with refactored proofs. The diff is a bit messy, but it's easy to understand with the right point-of-view: 1. lemmas which require linear orders are grouped into their own sections below the corresponding sections for partially ordered fields 2. proofs are refactored with the weaker hypotheses 3. a few lemmas near the top didn't actually need `IsStrictOrderedRing`, so those are grouped at the top. 4. The only new declarations added are `inv_lt_zero'` and `inv_nonpos'`, no others were deleted or changed (aside from weakening type class assumptions). 5. The positivity extension at the bottom of the file has its type class requirements weakened so that it applies in more contexts. Co-authored-by: Jireh Loreaux --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
180/131 Mathlib/Algebra/Order/Field/Basic.lean 1 6 ['github-actions', 'j-loreaux', 'leanprover-radar', 'mathlib4-merge-conflict-bot', 'themathqueen'] dagurtomas
assignee:dagurtomas
2-60831
2 days ago
2-60859
2 days ago
19-65938
19 days
33531 harahu
author:harahu
doc(CategoryTheory): fix typos Fix typos and staleness in docs. The issues were found and corrected by Codex. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-category-theory 210/208 Mathlib/CategoryTheory/Abelian/Basic.lean,Mathlib/CategoryTheory/Abelian/DiagramLemmas/Four.lean,Mathlib/CategoryTheory/Abelian/DiagramLemmas/KernelCokernelComp.lean,Mathlib/CategoryTheory/Abelian/Exact.lean,Mathlib/CategoryTheory/Abelian/Ext.lean,Mathlib/CategoryTheory/Abelian/FreydMitchell.lean,Mathlib/CategoryTheory/Abelian/GrothendieckAxioms/Connected.lean,Mathlib/CategoryTheory/Abelian/GrothendieckAxioms/FunctorCategory.lean,Mathlib/CategoryTheory/Abelian/GrothendieckCategory/ColimCoyoneda.lean,Mathlib/CategoryTheory/Abelian/GrothendieckCategory/Subobject.lean,Mathlib/CategoryTheory/Abelian/Injective/Basic.lean,Mathlib/CategoryTheory/Abelian/Monomorphisms.lean,Mathlib/CategoryTheory/Abelian/NonPreadditive.lean,Mathlib/CategoryTheory/Abelian/Opposite.lean,Mathlib/CategoryTheory/Abelian/Projective/Ext.lean,Mathlib/CategoryTheory/Abelian/Projective/Extend.lean,Mathlib/CategoryTheory/Abelian/Projective/Resolution.lean,Mathlib/CategoryTheory/Abelian/Pseudoelements.lean,Mathlib/CategoryTheory/Abelian/Refinements.lean,Mathlib/CategoryTheory/Abelian/SerreClass/Basic.lean,Mathlib/CategoryTheory/Action/Basic.lean,Mathlib/CategoryTheory/Action/Limits.lean,Mathlib/CategoryTheory/Adjunction/Evaluation.lean,Mathlib/CategoryTheory/Bicategory/Adjunction/Basic.lean,Mathlib/CategoryTheory/Bicategory/Functor/Cat/ObjectProperty.lean,Mathlib/CategoryTheory/Bicategory/Functor/Lax.lean,Mathlib/CategoryTheory/Bicategory/Functor/LocallyDiscrete.lean,Mathlib/CategoryTheory/Bicategory/Functor/Prelax.lean,Mathlib/CategoryTheory/Bicategory/Functor/StrictlyUnitary.lean,Mathlib/CategoryTheory/Bicategory/LocallyGroupoid.lean,Mathlib/CategoryTheory/Bicategory/NaturalTransformation/Oplax.lean,Mathlib/CategoryTheory/Bicategory/Product.lean,Mathlib/CategoryTheory/CatCommSq.lean,Mathlib/CategoryTheory/Category/ULift.lean,Mathlib/CategoryTheory/Comma/CardinalArrow.lean,Mathlib/CategoryTheory/Comma/Presheaf/Basic.lean,Mathlib/CategoryTheory/ComposableArrows/Basic.lean,Mathlib/CategoryTheory/ConcreteCategory/Basic.lean,Mathlib/CategoryTheory/Core.lean,Mathlib/CategoryTheory/Enriched/Basic.lean,Mathlib/CategoryTheory/Enriched/Limits/HasConicalPullbacks.lean,Mathlib/CategoryTheory/FiberedCategory/Fiber.lean,Mathlib/CategoryTheory/FinCategory/AsType.lean,Mathlib/CategoryTheory/Functor/KanExtension/Basic.lean,Mathlib/CategoryTheory/Functor/ReflectsIso/Balanced.lean,Mathlib/CategoryTheory/Functor/Trifunctor.lean,Mathlib/CategoryTheory/Galois/Basic.lean,Mathlib/CategoryTheory/Galois/GaloisObjects.lean,Mathlib/CategoryTheory/Galois/Prorepresentability.lean,Mathlib/CategoryTheory/Generator/Basic.lean,Mathlib/CategoryTheory/GradedObject/Bifunctor.lean,Mathlib/CategoryTheory/GradedObject/Trifunctor.lean,Mathlib/CategoryTheory/Groupoid/Subgroupoid.lean,Mathlib/CategoryTheory/Groupoid/VertexGroup.lean,Mathlib/CategoryTheory/Idempotents/FunctorExtension.lean,Mathlib/CategoryTheory/IsomorphismClasses.lean,Mathlib/CategoryTheory/Limits/ConcreteCategory/WithAlgebraicStructures.lean,Mathlib/CategoryTheory/Limits/Constructions/Equalizers.lean,Mathlib/CategoryTheory/Limits/Creates.lean,Mathlib/CategoryTheory/Limits/ExactFunctor.lean,Mathlib/CategoryTheory/Limits/FilteredColimitCommutesFiniteLimit.lean,Mathlib/CategoryTheory/Limits/FintypeCat.lean,Mathlib/CategoryTheory/Limits/FormalCoproducts.lean,Mathlib/CategoryTheory/Limits/FunctorCategory/Shapes/Pullbacks.lean,Mathlib/CategoryTheory/Limits/MonoCoprod.lean,Mathlib/CategoryTheory/Limits/Preorder.lean,Mathlib/CategoryTheory/Limits/Preserves/Shapes/Images.lean,Mathlib/CategoryTheory/Limits/Preserves/Shapes/Pullbacks.lean,Mathlib/CategoryTheory/Limits/Preserves/Shapes/Square.lean,Mathlib/CategoryTheory/Limits/Shapes/ConcreteCategory.lean,Mathlib/CategoryTheory/Limits/Shapes/Images.lean,Mathlib/CategoryTheory/Limits/Shapes/Opposites/Filtered.lean,Mathlib/CategoryTheory/Limits/Shapes/Preorder/PrincipalSeg.lean,Mathlib/CategoryTheory/Limits/Shapes/Preorder/WellOrderContinuous.lean,Mathlib/CategoryTheory/Limits/Shapes/Pullback/PullbackCone.lean,Mathlib/CategoryTheory/Limits/Shapes/Pullback/Square.lean,Mathlib/CategoryTheory/Limits/Shapes/Reflexive.lean,Mathlib/CategoryTheory/Limits/Shapes/RegularMono.lean,Mathlib/CategoryTheory/Limits/Shapes/SplitCoequalizer.lean,Mathlib/CategoryTheory/Limits/Shapes/WidePullbacks.lean,Mathlib/CategoryTheory/Limits/Types/ColimitType.lean,Mathlib/CategoryTheory/Limits/Types/ColimitTypeFiltered.lean,Mathlib/CategoryTheory/Limits/Types/Pushouts.lean,Mathlib/CategoryTheory/Linear/Yoneda.lean,Mathlib/CategoryTheory/Localization/Construction.lean,Mathlib/CategoryTheory/Localization/DerivabilityStructure/Basic.lean,Mathlib/CategoryTheory/Localization/DerivabilityStructure/OfFunctorialResolutions.lean,Mathlib/CategoryTheory/Localization/Predicate.lean,Mathlib/CategoryTheory/Localization/Quotient.lean,Mathlib/CategoryTheory/Monoidal/Action/LinearFunctor.lean,Mathlib/CategoryTheory/Monoidal/Braided/Basic.lean,Mathlib/CategoryTheory/Monoidal/Closed/Basic.lean,Mathlib/CategoryTheory/Monoidal/Closed/FunctorCategory/Groupoid.lean,Mathlib/CategoryTheory/Monoidal/Conv.lean,Mathlib/CategoryTheory/Monoidal/DayConvolution.lean,Mathlib/CategoryTheory/Monoidal/DayConvolution/DayFunctor.lean,Mathlib/CategoryTheory/Monoidal/Discrete.lean,Mathlib/CategoryTheory/Monoidal/Limits/Preserves.lean,Mathlib/CategoryTheory/MorphismProperty/Composition.lean,Mathlib/CategoryTheory/MorphismProperty/Concrete.lean 132 5 ['github-actions', 'harahu', 'joelriou'] nobody
2-60534
2 days ago
2-60551
2 days ago
4-50316
4 days
33620 harahu
author:harahu
doc(Algebra): fix file refs Update some stale file references. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
9/7 Mathlib/Algebra/Group/Subsemigroup/Operations.lean,Mathlib/Algebra/Group/Units/Defs.lean,Mathlib/Algebra/HierarchyDesign.lean,Mathlib/Algebra/Module/Presentation/Differentials.lean,Mathlib/Algebra/Ring/Action/End.lean 5 1 ['github-actions'] nobody
2-59517
2 days ago
2-61214
2 days ago
2-61257
2 days
33612 xgenereux
author:xgenereux
feat(ValuationSubring): fieldTop Given a field `K`, the top element of `ValuationSubring K` is `K`, so top is also a field. Note: I fear this would be a bad instance so I have marked this as an abbrev for now. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 10/0 Mathlib/RingTheory/Valuation/ValuationSubring.lean 1 5 ['github-actions', 'vihdzp', 'xgenereux'] nobody
2-57163
2 days ago
2-70682
2 days ago
2-70720
2 days
30144 alreadydone
author:alreadydone
feat(Data/Nat): kernel reducible binaryRec + Redefine `Nat.binaryRec` to allow kernel reduction. + Move some lemmas from Data/Nat/Bitwise to Data/Nat/BinaryRec. + Use `nsmulBinRec` for nsmul/zsmul on elliptic curves. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra t-data
label:t-algebra$
119/60 Mathlib/Algebra/Group/Defs.lean,Mathlib/Algebra/Group/Prod.lean,Mathlib/AlgebraicGeometry/EllipticCurve/Affine/Point.lean,Mathlib/Data/Nat/BinaryRec.lean,Mathlib/Data/Nat/BitIndices.lean,Mathlib/Data/Nat/Bits.lean,Mathlib/Data/Nat/Bitwise.lean,Mathlib/Data/Nat/Digits/Defs.lean,Mathlib/Data/Nat/Size.lean 9 12 ['alreadydone', 'astrainfinita', 'github-actions', 'leanprover-bot', 'leanprover-community-mathlib4-bot', 'mathlib4-merge-conflict-bot'] pechersky
assignee:pechersky
2-46339
2 days ago
2-70877
2 days ago
62-23675
62 days
33458 NoneMore
author:NoneMore
feat(ModelTheory): add lifting for embeddings to languages with constants Prepare for a generalized Tarski-Vaught test with a set as input instead of a substructure. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic new-contributor 46/0 Mathlib/ModelTheory/ElementaryMaps.lean,Mathlib/ModelTheory/LanguageMap.lean 2 1 ['github-actions'] fpvandoorn
assignee:fpvandoorn
2-43898
2 days ago
6-74831
6 days ago
6-74868
6 days
33478 anishrajeev
author:anishrajeev
feat(ModelTheory): define a subset of the topology over complete types Define a subset of the Stone Space over a language expanded with countably many constants. Define the proposition to indicate if a language is countable. The subset's density and openness is a future goal to prove (have a branch where it is almost finished), in pursuit of formalizing the proof of the Omitting Types Theorem via properties of Baire spaces. [ ] depends on: #32215 [ ] depends on: #32546 new-contributor 160/1 Mathlib.lean,Mathlib/ModelTheory/Topology/Types.lean,Mathlib/ModelTheory/Types.lean,Mathlib/Tactic/Linter/DirectoryDependency.lean 4 5 ['NoneMore', 'anishrajeev', 'github-actions'] RemyDegenne
assignee:RemyDegenne
2-43895
2 days ago
6-38706
6 days ago
6-38686
6 days
33487 gasparattila
author:gasparattila
feat(Topology/UniformSpace): `SetRel.{inv,image,preimage}` of `entourageProd` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology 15/0 Mathlib/Topology/UniformSpace/Basic.lean 1 1 ['github-actions'] dagurtomas
assignee:dagurtomas
2-43893
2 days ago
5-76742
5 days ago
5-76781
5 days
33494 vihdzp
author:vihdzp
feat(RingTheory/HahnSeries/Basic): more theorems on `order`/`orderTop` We also deprecate various badly named or overspecific theorems relating to `ofSuppBddBelow`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 64/32 Mathlib/Algebra/Vertex/VertexOperator.lean,Mathlib/RingTheory/HahnSeries/Basic.lean,Mathlib/RingTheory/LaurentSeries.lean 3 1 ['github-actions'] mattrobball
assignee:mattrobball
2-43892
2 days ago
5-47943
5 days ago
5-47929
5 days
33643 vihdzp
author:vihdzp
feat: `r < stdPart x → r < x` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
25/4 Mathlib/Algebra/Order/Ring/StandardPart.lean 1 1 ['github-actions'] nobody
2-40284
2 days ago
2-41613
2 days ago
2-41646
2 days
33649 vihdzp
author:vihdzp
feat(Analysis/Real/Hyperreal): more lemmas on `ω` and `ε` I've moved these around a bit, so as to ensure the lemmas about each constant are next to each other. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra large-import
label:t-algebra$
116/30 Mathlib/Algebra/Order/AddGroupWithTop.lean,Mathlib/Algebra/Order/Ring/Archimedean.lean,Mathlib/Algebra/Order/Ring/StandardPart.lean,Mathlib/Analysis/Real/Hyperreal.lean 4 6 ['github-actions', 'vihdzp', 'wwylele'] nobody
2-27701
2 days ago
2-34016
2 days ago
2-35494
2 days
33584 kim-em
author:kim-em
fix(Tactic/TacticAnalysis): analyze tactics inside `have ... := by ...` This PR fixes TacticAnalysis to correctly process tactics inside term-level `by` blocks such as `have h := by ...`. Previously, these tactics were missed. The fix is simple: move the sequencing operator check before the `.original` head info check. This is needed because the `tacticSeq` nodes inside `have := by` have synthetic source info rather than `.original`. See: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/TacticAnalysis.20ignores.20tactics.20in.20have/near/565486129 🤖 Prepared with Claude Code t-meta 41/7 Mathlib/Tactic/TacticAnalysis.lean,MathlibTest/TacticAnalysis.lean 2 50 ['Vierkantor', 'adomani', 'github-actions', 'kim-em'] nobody
2-26379
2 days ago
2-26379
2 days ago
2-46260
2 days
31706 Thmoas-Guan
author:Thmoas-Guan
feat(Algebra/ModuleCat): `ModuleCat.uliftFunctor` Add `ModuleCat.uliftFunctor` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
108/0 Mathlib.lean,Mathlib/Algebra/Category/ModuleCat/Ulift.lean 2 15 ['Thmoas-Guan', 'dagurtomas', 'erdOne', 'github-actions', 'mathlib4-merge-conflict-bot', 'robin-carlier'] mattrobball
assignee:mattrobball
2-23202
2 days ago
10-79855
10 days ago
21-73567
21 days
33657 vihdzp
author:vihdzp
chore(SetTheory/Cardinal/Arithmetic): switch `lift.{max u w} x = lift.{max v w} y` to `lift.{u} x = lift.{v} y` --- Lean can't often infer the extra `w` universe otherwise. Oh, if only we had some sort of `liftEq` predicate so we didn't have to bother with `lift` at all. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-set-theory 13/13 Mathlib/SetTheory/Cardinal/Arithmetic.lean,Mathlib/SetTheory/Cardinal/Basic.lean 2 1 ['github-actions'] nobody
2-22239
2 days ago
2-22241
2 days ago
2-22277
2 days
30484 vihdzp
author:vihdzp
refactor: override `≤` and `<` in `Function.Injective.semilatticeSup`, etc. These constructors now take `LE` and `LT` instance arguments, and proofs that the "induced" relations are equal. This matches the behavior for all other data fields of the same constructors, which avoids diamonds which could otherwise arise. To recover the old behavior, you can instantiate `LE` and `LT` instances through `PartialOrder.lift` (if they don't exist already), and set the `le` and `lt` fields to `Iff.rfl`. --- I seem to have (somehow?) changed a syntactic equality on fractional ideals - given that this golfs various proofs and even removes a porting note, I think this change is desirable. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-order 396/380 Mathlib/Algebra/Lie/Submodule.lean,Mathlib/Algebra/Module/Injective.lean,Mathlib/Algebra/Order/Group/Ideal.lean,Mathlib/Algebra/Order/Kleene.lean,Mathlib/Analysis/Convex/Cone/Dual.lean,Mathlib/Analysis/Normed/Group/Seminorm.lean,Mathlib/Analysis/Seminorm.lean,Mathlib/CategoryTheory/Sites/Precoverage.lean,Mathlib/Combinatorics/Digraph/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Basic.lean,Mathlib/Combinatorics/SimpleGraph/Finsubgraph.lean,Mathlib/Combinatorics/SimpleGraph/Subgraph.lean,Mathlib/Combinatorics/Young/YoungDiagram.lean,Mathlib/FieldTheory/Galois/GaloisClosure.lean,Mathlib/GroupTheory/GroupAction/SubMulAction.lean,Mathlib/MeasureTheory/MeasurableSpace/MeasurablyGenerated.lean,Mathlib/ModelTheory/Definability.lean,Mathlib/NumberTheory/NumberField/FractionalIdeal.lean,Mathlib/Order/BooleanAlgebra/Basic.lean,Mathlib/Order/BooleanSubalgebra.lean,Mathlib/Order/CompleteBooleanAlgebra.lean,Mathlib/Order/CompleteLattice/Basic.lean,Mathlib/Order/CompleteLattice/Lemmas.lean,Mathlib/Order/CompleteSublattice.lean,Mathlib/Order/Concept.lean,Mathlib/Order/Disjoint.lean,Mathlib/Order/Heyting/Basic.lean,Mathlib/Order/Heyting/Regular.lean,Mathlib/Order/Hom/Bounded.lean,Mathlib/Order/Hom/BoundedLattice.lean,Mathlib/Order/Hom/Lattice.lean,Mathlib/Order/Interval/Basic.lean,Mathlib/Order/Lattice.lean,Mathlib/Order/Nucleus.lean,Mathlib/Order/Sublattice.lean,Mathlib/Order/UpperLower/CompleteLattice.lean,Mathlib/RepresentationTheory/Subrepresentation.lean,Mathlib/RingTheory/DedekindDomain/Different.lean,Mathlib/RingTheory/DedekindDomain/Factorization.lean,Mathlib/RingTheory/DedekindDomain/Ideal/Basic.lean,Mathlib/RingTheory/DividedPowers/SubDPIdeal.lean,Mathlib/RingTheory/Filtration.lean,Mathlib/RingTheory/FractionalIdeal/Basic.lean,Mathlib/RingTheory/FractionalIdeal/Extended.lean,Mathlib/RingTheory/FractionalIdeal/Inverse.lean,Mathlib/RingTheory/FractionalIdeal/Operations.lean,Mathlib/RingTheory/GradedAlgebra/Homogeneous/Ideal.lean,Mathlib/Topology/Algebra/Group/ClosedSubgroup.lean,Mathlib/Topology/Algebra/Group/GroupTopology.lean,Mathlib/Topology/Algebra/Module/ClosedSubmodule.lean,Mathlib/Topology/Algebra/OpenSubgroup.lean,Mathlib/Topology/ContinuousMap/Bounded/Normed.lean,Mathlib/Topology/ContinuousMap/CompactlySupported.lean,Mathlib/Topology/ContinuousMap/Ordered.lean,Mathlib/Topology/DiscreteQuotient.lean,Mathlib/Topology/Sets/Closeds.lean,Mathlib/Topology/Sets/Compacts.lean,Mathlib/Topology/Sets/Opens.lean,Mathlib/Topology/Sets/Order.lean 59 44 ['Vierkantor', 'YaelDillies', 'github-actions', 'jcommelin', 'leanprover-bot', 'leanprover-radar', 'mathlib4-merge-conflict-bot', 'plp127', 'vihdzp'] bryangingechen
assignee:bryangingechen
2-20712
2 days ago
2-22432
2 days ago
46-26868
46 days
33654 vihdzp
author:vihdzp
chore: `LinearOrderedCommMonoidWithZero` extends `ZeroLEOneClass` We also remove a duplicate `ZeroLEOneClass` instance on `CanonicallyOrderedAdd`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
2/12 Mathlib/Algebra/Order/GroupWithZero/Canonical.lean 1 3 ['github-actions', 'leanprover-radar', 'vihdzp'] nobody
2-16470
2 days ago
2-18009
2 days ago
2-24450
2 days
31046 Thmoas-Guan
author:Thmoas-Guan
feat(Homology) : compatibility of map between `Ext` In this PR, we proved the compatibility of map between `Ext` induced by exact functor with 1: `mk_0` 2: `comp` 3: `extClass` --- - [ ] depends on: #31707 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) merge-conflict t-category-theory 409/3 Mathlib.lean,Mathlib/Algebra/Homology/DerivedCategory/ExactFunctor.lean,Mathlib/Algebra/Homology/DerivedCategory/Ext/Map.lean,Mathlib/Algebra/Homology/DerivedCategory/ShortExact.lean,Mathlib/Algebra/Homology/HomotopyCategory.lean,Mathlib/Algebra/Homology/HomotopyCategory/Pretriangulated.lean,Mathlib/Algebra/Homology/HomotopyCategory/ShortExact.lean,Mathlib/Algebra/Homology/HomotopyCategory/SingleFunctors.lean,Mathlib/CategoryTheory/Linear/LinearFunctor.lean,Mathlib/CategoryTheory/Shift/CommShift.lean,Mathlib/CategoryTheory/Shift/ShiftedHom.lean 11 7 ['Thmoas-Guan', 'github-actions', 'joelriou', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] eric-wieser
assignee:eric-wieser
2-76364
2 days ago
2-76365
2 days ago
4-3344
4 days
33662 Pjotr5
author:Pjotr5
feat(Algebra/Order/BigOperators/Expect): add lemmas and strict variants ### Summary - Combine `le_expect_nonempty_of_subadditive` and `le_expect_of_subadditive` into a single lemma `le_expect_of_subadditive`. The extra assumptions `(hs : s.Nonempty)` and `(h_zero : m 0 = 0)` are unnecessary (since `m 0 = 0` follows from `h_div`). This requires a small downstream update to `Mathlib/Analysis/RCLike/Basic.lean` (`norm_expect_le`). - Add strict-inequality variants: `expect_lt_expect`, `expect_lt`, `lt_expect`. - Add existence lemmas: `exists_le_of_expect_le_expect`, `exists_le_of_le_expect`, `exists_le_of_expect_le`, and `exists_lt_of_expect_lt_expect`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor 46/16 Mathlib/Algebra/Order/BigOperators/Expect.lean,Mathlib/Analysis/RCLike/Basic.lean 2 1 ['github-actions'] nobody
2-11639
2 days ago
2-14216
2 days ago
2-14198
2 days
31891 jsm28
author:jsm28
feat(Geometry/Euclidean/Sphere/OrthRadius): lemmas for setting up and using polars Add further lemmas about `orthRadius` that are of use in setting up and using poles and polars. In particular, `ncard_inter_orthRadius_eq_two_of_dist_lt_radius` is the key part of showing that, in two dimensions, there are exactly two tangents to a circle from a point outside that circle (where the points of tangency lie on the polar of the point from which the two tangents are drawn). --- Feel free to golf the proof of `ncard_inter_orthRadius_eq_two_of_dist_lt_radius`, it could probably be rather shorter. --- - [ ] depends on: #32296 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-euclidean-geometry 185/7 Mathlib/Geometry/Euclidean/Sphere/OrthRadius.lean,Mathlib/Geometry/Euclidean/Sphere/Tangent.lean 2 26 ['eric-wieser', 'github-actions', 'jsm28', 'mathlib4-dependent-issues-bot'] JovanGerb
assignee:JovanGerb
2-6081
2 days ago
38-4045
1 month ago
47-48793
47 days
32316 Thmoas-Guan
author:Thmoas-Guan
feat(Homology/ModuleCat): Dimension Shifting tools in ModuleCat In this PR we present some dimension shifting tools in `ModuleCat`. --- - [x] depends on: #32312 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-category-theory t-algebra
label:t-algebra$
132/0 Mathlib.lean,Mathlib/Algebra/Category/ModuleCat/Ext/DimensionShifting.lean,Mathlib/Algebra/Homology/DerivedCategory/Ext/EnoughInjectives.lean,Mathlib/Algebra/Homology/DerivedCategory/Ext/EnoughProjectives.lean,Mathlib/Algebra/Homology/ShortComplex/ModuleCat.lean,Mathlib/RingTheory/Noetherian/Basic.lean 6 20 ['Thmoas-Guan', 'erdOne', 'github-actions', 'jcommelin', 'joelriou', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] joelriou
assignee:joelriou
2-4563
2 days ago
10-10263
10 days ago
10-36053
10 days
32959 CBirkbeck
author:CBirkbeck
feat(NumberTheory/ModularForms/QExpansion): define qExpansion ring hom and some more API We construct the ring homomorphism from the graded ring of modular forms to power series. We prove develop some basic API for this and also prove the qExpansion coefficients are unique, which is useful to extracting the actual qExpansions of Eisenstein series. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-number-theory 410/6 Mathlib/Analysis/Calculus/Deriv/Mul.lean,Mathlib/Analysis/Calculus/IteratedDeriv/Lemmas.lean,Mathlib/NumberTheory/ModularForms/QExpansion.lean 3 1 ['github-actions'] loefflerd
assignee:loefflerd
1-85412
1 day ago
1-86334
1 day ago
22-82076
22 days
33431 gululu996-ui
author:gululu996-ui
feat(Combinatorics/SimpleGraph/Bipartite): characterize bipartite simplegraphs by even cycles Add the classical characterization of bipartite simple graphs: a simple graph is bipartite if and only if every cycle has even length. Previously, mathlib has the definition of `IsBipartite` for `SimpleGraph` and various lemmas about bipartite graphs, but it does not provide this equivalence in a single theorem, so users have to reprove or reassemble it from existing results. Prove the forward direction by showing a 2-coloring alternates along any walk, so every cycle must have even length. Prove the converse by showing that if an odd cycle exists then no bipartition is possible, hence if all cycles are even the graph admits a bipartition. t-combinatorics new-contributor 185/1 Mathlib/Combinatorics/SimpleGraph/Bipartite.lean 1 3 ['NickAdfor', 'github-actions'] nobody
1-83590
1 day ago
4-465
4 days ago
8-2145
8 days
33592 nielstron
author:nielstron
feat(Computability/ContextFreeGrammar): mapping between two types of nonterminal symbols --- This PR picks up https://github.com/leanprover-community/mathlib4/pull/15895 and resolves the failing lemma by redefining Good symbols. I checked that https://github.com/leanprover-community/mathlib4/pull/13514 builds correctly when based on this build. PR for that is #33599 This is my first contribution please let me know of any changes I should outline. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-computability 162/0 Mathlib/Computability/ContextFreeGrammar.lean 1 1 ['github-actions', 'madvorak'] nobody
1-79411
1 day ago
3-2385
3 days ago
3-2910
3 days
33606 ScottCarnahan
author:ScottCarnahan
feat(Algebra/Lie): basics of loop algebras This PR introduces the Lie algebra of polynomial loops in a base Lie algebra, together with the 2-cochain induced by a symmetric bilinear form on the base Lie algebra. --- I am a bit dissatisfied with the restriction of `twoCochain_of_Bilinear` to integers, but I couldn't find a good substitute for `Int.natAbs` that joined elements with their negatives. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
206/1 Mathlib.lean,Mathlib/Algebra/BigOperators/Finprod.lean,Mathlib/Algebra/Lie/BaseChange.lean,Mathlib/Algebra/Lie/Extension.lean,Mathlib/Algebra/Lie/Loop.lean 5 1 ['github-actions'] ocfnash
assignee:ocfnash
1-76734
1 day ago
2-74888
2 days ago
2-74921
2 days
31560 AntoineChambert-Loir
author:AntoineChambert-Loir
feat(Topology/Sion): the minimax theorem of von Neumann - Sion Prove `Sion.exists_isSaddlePointOn` : Let X and Y be convex subsets of topological vector spaces E and F, X being moreover compact, and let f : X × Y → ℝ be a function such that - for all x, f(x, ⬝) is upper semicontinuous and quasiconcave - for all y, f(⬝, y) is lower semicontinuous and quasiconvex Then inf_x sup_y f(x,y) = sup_y inf_x f(x,y). The classical case of the theorem assumes that f is continuous, f(x, ⬝) is concave, f(⬝, y) is convex. As a particular case, one get the von Neumann theorem where f is bilinear and E, F are finite dimensional. We follow the proof of Komiya (1988). ## Remark on implementation * The essential part of the proof holds for a function `f : X → Y → β`, where `β` is a complete dense linear order. * We have written part of it for just a dense linear order, * On the other hand, if the theorem holds for such `β`, it must hold for any linear order, for the reason that any linear order embeds into a complete dense linear order. However, this result does not seem to be known to Mathlib. * When `β` is `ℝ`, one can use `Real.toEReal` and one gets a proof for `ℝ`. ## TODO Give particular important cases (eg, bilinear maps in finite dimension). Co-authored with @ADedecker --- - [x] depends on: #31548 - [x] depends on: #31547 - [x] depends on: #31558 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology 741/0 Mathlib.lean,Mathlib/Data/EReal/Basic.lean,Mathlib/Topology/Semicontinuity/Basic.lean,Mathlib/Topology/Sion.lean,docs/references.bib 5 6 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] dwrensha, kmill, thorimur
assignee:kmill assignee:dwrensha assignee:thorimur
20-48445
20 days ago
20-48669
20 days ago
28-52525
28 days
33672 euprunin
author:euprunin
chore: golf using `grind`. add `grind` annotations. --- The goal of this golfing PR is to decrease the number of times lemmas are called explicitly (replacing calls to lemmas with calls to tactics). Any decrease in compilation time is a welcome side effect, although it is not a primary objective. Trace profiling results (shown if ≥10 ms before or after): * `Orientation.nonneg_inner_and_areaForm_eq_zero_iff_sameRay`: 287 ms before, 336 ms after * `PFunctor.liftr_iff`: 49 ms before, 93 ms after * `IsAdjoinRootMonic.coeff_root_pow`: 119 ms before, 267 ms after This golfing PR is batched under the following guidelines: * Up to ~5 changed files per PR * Up to ~25 changed declarations per PR * Up to ~100 changed lines per PR --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 9/33 Mathlib/Analysis/InnerProductSpace/TwoDim.lean,Mathlib/Data/PFunctor/Univariate/Basic.lean,Mathlib/RingTheory/IsAdjoinRoot.lean 3 3 ['euprunin', 'github-actions', 'leanprover-radar'] nobody
1-69090
1 day ago
1-70889
1 day ago
1-70862
1 day
33286 euprunin
author:euprunin
chore: golf using `grind` --- The goal of this golfing PR is to decrease the number of times lemmas are called explicitly (replacing calls to lemmas with calls to tactics). Any decrease in compilation time is a welcome side effect, although it is not a primary objective. Trace profiling results (shown if ≥10 ms before or after): * `Finset.memberSubfamily_union_nonMemberSubfamily`: 11 ms before, 116 ms after * `AkraBazziRecurrence.GrowsPolynomially.eventually_atTop_nonneg_or_nonpos`: 1181 ms before, 1194 ms after * `Equiv.Perm.support_congr`: <10 ms before, 38 ms after * `Equiv.Perm.subtypeCongr.trans`: 13 ms before, 35 ms after * `preCantorSet_antitone`: 766 ms before, 371 ms after 🎉 This golfing PR is batched under the following guidelines: * Up to ~5 changed files per PR * Up to ~25 changed declarations per PR * Up to ~100 changed lines per PR --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 6/28 Mathlib/Computability/AkraBazzi/GrowsPolynomially.lean,Mathlib/GroupTheory/Perm/Support.lean,Mathlib/Logic/Equiv/Basic.lean,Mathlib/Topology/Instances/CantorSet.lean 4 5 ['euprunin', 'github-actions', 'vihdzp'] thorimur
assignee:thorimur
1-65562
1 day ago
1-66181
1 day ago
13-39451
13 days
32735 Jlh18
author:Jlh18
refactor: move `CategoryTheory.Category.Grpd` to `CategoryTheory.Groupoid.Grpd.Basic` Step one of several PRs, stemming from #29283 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) file-removed 3/4 Mathlib.lean,Mathlib/AlgebraicTopology/FundamentalGroupoid/Basic.lean,Mathlib/CategoryTheory/Groupoid/FreeGroupoidOfCategory.lean,Mathlib/CategoryTheory/Groupoid/Grpd/Basic.lean 4 3 ['Jlh18', 'github-actions', 'mathlib4-merge-conflict-bot'] nobody
1-64079
1 day ago
1-64098
1 day ago
8-1062
8 days
29186 winstonyin
author:winstonyin
feat: IsIntegralCurve for solutions to ODEs I define `IsIntegralCurve` etc. for solutions to ODEs on vector spaces. The translation and scaling lemmas are also included. This parallels `IsMIntegralCurve` etc. for manifolds. Moved from #26534. - [x] depends on: #26563 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-differential-geometry t-analysis t-dynamics 312/100 Mathlib.lean,Mathlib/Analysis/ODE/Basic.lean,Mathlib/Analysis/ODE/Transform.lean,Mathlib/Geometry/Manifold/IntegralCurve/Basic.lean,Mathlib/Geometry/Manifold/IntegralCurve/Transform.lean 5 9 ['github-actions', 'grunweg', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'sgouezel'] sgouezel
assignee:sgouezel
1-63884
1 day ago
1-66026
1 day ago
101-84992
101 days
33656 metakunt
author:metakunt
feat(Data/Nat/Choose): Add sum_range_multichoose t-data 11/0 Mathlib/Data/Nat/Choose/Sum.lean 1 5 ['eric-wieser', 'github-actions', 'metakunt'] nobody
1-60356
1 day ago
2-22735
2 days ago
2-22777
2 days
33635 plp127
author:plp127
feat(Tactic/Set): use `binderIdent` instead of `ident` This let both `a` and `h` be replaced with `_` in the syntax `set a := val with ← h` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta 16/2 Mathlib/Tactic/Set.lean,MathlibTest/Set.lean 2 3 ['JovanGerb', 'github-actions', 'plp127'] nobody
1-60092
1 day ago
2-52189
2 days ago
2-52169
2 days
33613 DavidLedvinka
author:DavidLedvinka
feat(Probability): `UniformOn_univ_instIsProbabilityMeasure` It is convenient to have an instance of `IsProbabilityMeasure` on a uniform distribution on `.univ` (to avoid the need for `haveI` statements). There is perhaps an argument for `abbrev uniform := uniformOn (.univ : Set Ω)` but I have not implemented this in this PR. t-measure-probability 11/0 Mathlib/Probability/UniformOn.lean 1 1 ['github-actions'] nobody
1-58147
1 day ago
1-58147
1 day ago
1-58133
1 day
33216 stepan2698-cpu
author:stepan2698-cpu
feat: Schur's lemma over an algebraically closed field Adds a new file with facts about algebra representations. Proves Schur's lemma (any endomorphism of an algebra representation over an algebraically closed field is scalar) and proves that every finite-dimensional representation of a commutative algebra over an algebraically closed field is one-dimensional. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra new-contributor
label:t-algebra$
80/0 Mathlib.lean,Mathlib/RepresentationTheory/AlgebraRepresentation/Basic.lean 2 6 ['copilot-pull-request-reviewer', 'github-actions'] riccardobrasca
assignee:riccardobrasca
1-56606
1 day ago
16-34389
16 days ago
16-34426
16 days
32856 stepan2698-cpu
author:stepan2698-cpu
feat: definition of an irreducible representation Define irreducible monoid representations over a field and prove that a monoid representation is irreducible iff the corresponding module over the monoid algebra is simple. t-algebra new-contributor
label:t-algebra$
129/10 Mathlib.lean,Mathlib/RepresentationTheory/Irreducible.lean,Mathlib/RepresentationTheory/Subrepresentation.lean 3 21 ['Whysoserioushah', 'erdOne', 'github-actions', 'stepan2698-cpu'] kim-em
assignee:kim-em
1-56577
1 day ago
25-55329
25 days ago
25-55363
25 days
33637 themathqueen
author:themathqueen
feat(Analysis/Matrix/Order): `det (abs A) = |det A|` and `det (sqrt A) = √(det A)` ... for Hermitian and positive semi-definite, respectively. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis 21/1 Mathlib/Analysis/Matrix/Order.lean,Mathlib/Data/Real/Sqrt.lean 2 3 ['github-actions', 'themathqueen'] nobody
1-54958
1 day ago
2-46840
2 days ago
2-46882
2 days
33668 Citronhat
author:Citronhat
feat(PMF): add lintegral formulas for PMF This PR introduces two lemmas describing the `lintegral` of a function with respect to the measure induced by a probability mass function: - `PMF.lintegral_eq_tsum` - `PMF.lintegral_eq_sum` These are the `ℝ≥0∞` analogues of the existing Bochner `integral` formulas `integral_eq_tsum` and `integral_eq_sum`. They could be useful for reasoning about expectations and integrability. In addition, the proof of `integral_eq_sum` is simplified by deriving it directly from `integral_eq_tsum` using `tsum_fintype`. t-measure-probability new-contributor 14/5 Mathlib/Probability/ProbabilityMassFunction/Integrals.lean 1 1 ['github-actions'] nobody
1-49044
1 day ago
1-82471
1 day ago
1-82512
1 day
33358 joelriou
author:joelriou
feat(Algebra/Homology): functoriality of `ProjectiveResolution.extMk` Given a fixed projective (resp. injective) resolution `R`, we obtain the functoriality of the constructor `R.extMk`. --- - [x] depends on: #32816 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-category-theory 126/8 Mathlib/Algebra/Homology/HomotopyCategory/HomComplex.lean,Mathlib/Algebra/Homology/HomotopyCategory/HomComplexShift.lean,Mathlib/Algebra/Homology/HomotopyCategory/HomComplexSingle.lean,Mathlib/CategoryTheory/Abelian/Injective/Ext.lean,Mathlib/CategoryTheory/Abelian/Projective/Ext.lean 5 5 ['github-actions', 'joelriou', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'robin-carlier'] nobody
4-83893
4 days ago
4-83893
4 days ago
5-13400
5 days
33492 YaelDillies
author:YaelDillies
feat(Algebra/MonoidAlgebra): `R[M][N] ≃+* R[N][M]` Prove that `R[M × N] ≃+* R[N][M]` and deduce that `R[M][N] ≃+* R[N][M]`. Add supporting `Finsupp` lemmas. The ugly proofs are transitional and will be reworked in and after #25273. --- - [x] depends on: #33516 - [x] depends on: #33521 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
125/12 Mathlib/Algebra/BigOperators/Finsupp/Basic.lean,Mathlib/Algebra/Group/Finsupp.lean,Mathlib/Algebra/MonoidAlgebra/Basic.lean,Mathlib/Algebra/MonoidAlgebra/Defs.lean,Mathlib/Algebra/MonoidAlgebra/MapDomain.lean 5 21 ['YaelDillies', 'eric-wieser', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] mattrobball
assignee:mattrobball
1-43894
1 day ago
4-59556
4 days ago
5-25956
5 days
33518 joelriou
author:joelriou
feat(CategoryTheory/Sites): fullness of `DescentData.pullFunctor` Let `F` be a prestack for a Grothendieck topology `J`, `f : X i ⟶ S` and `f' : X' j ⟶ S` be two families of morphisms. Assume that `f'` is a covering family for `J`, then functors `F.pullFunctor .. : F.DescentData f ⥤ F.DescentData f'` are full. (They are also faithful, but this shall be done in a separate PR #33256 where we also deduce characterizations of (pre)stacks for pretopologies.) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-category-theory 269/0 Mathlib.lean,Mathlib/CategoryTheory/Sites/Descent/Precoverage.lean 2 2 ['github-actions', 'joelriou'] jcommelin
assignee:jcommelin
1-43889
1 day ago
5-14268
5 days ago
5-14241
5 days
33524 ldct
author:ldct
fix: Rename constructors in Irrational.lean docstrings The old names have been deprecated and removed from the codebase, but the docstring still refers to them. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-number-theory 1/1 Mathlib/NumberTheory/Real/Irrational.lean 1 1 ['github-actions', 'vihdzp'] riccardobrasca
assignee:riccardobrasca
1-43888
1 day ago
4-75540
4 days ago
4-75573
4 days
33693 yoh-tanimoto
author:yoh-tanimoto
feat(Mathlib/Analysis/Normed/Module): add instances of `CompleteSpace` for `Submodules` and `ClosedSubmodule` add an instance of `CompleteSpace` for a `Submodule` of a Banach space `[NormedField 𝕜] [NormedAddCommGroup E] [NormedSpace 𝕜 E] [CompleteSpace E]` which `IsClosed`. In this relation, convert a lemma showing `IsClosed` to an instance for `ClosedSubmodule`. motivation: Together with #28709, this makes it automatic that a `ClosedSubmodule` in a Hilbert space `HasOrthogonalProjection`. discussion: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/.60CompleteSpace.60.20for.20closed.20subtypes.20in.20a.20.60CompleteSpace.60 5/2 Mathlib/Analysis/Normed/Module/Basic.lean,Mathlib/Topology/Algebra/Module/ClosedSubmodule.lean 2 2 ['github-actions'] nobody
1-42374
1 day ago
1-44358
1 day ago
1-44331
1 day
33491 themathqueen
author:themathqueen
feat(Analysis/InnerProductSpace): linear map is positive iff it equals the sum of rank-one operators ... and equality of nonzero rank-one operators means the elements are colinear. --- The proof of `rankOne_normalize_eq_rankOne_normalize_iff` is kinda messy. Feel free to golf. - [x] depends on: #33439 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis 97/5 Mathlib/Analysis/InnerProductSpace/LinearMap.lean,Mathlib/Analysis/InnerProductSpace/Positive.lean,Mathlib/Analysis/InnerProductSpace/Symmetric.lean 3 3 ['github-actions', 'mathlib4-dependent-issues-bot', 'themathqueen'] nobody
1-42257
1 day ago
1-62710
1 day ago
1-62703
1 day
33658 vihdzp
author:vihdzp
refactor(RingTheory/Valuation/ValuativeRel/Basic): fix theorem names for multiplication We rename `vle_mul_right` to `mul_vle_mul_left` and reorder its arguments to match `mul_le_mul_left`, and other analogous changes. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 61/62 Mathlib/RingTheory/Valuation/ValuativeRel/Basic.lean,Mathlib/RingTheory/Valuation/ValuativeRel/Trivial.lean 2 2 ['JovanGerb', 'github-actions'] nobody
1-41565
1 day ago
2-18123
2 days ago
2-18157
2 days
33501 SnirBroshi
author:SnirBroshi
feat(Combinatorics/SimpleGraph/Finite): degrees for infinite graphs - Redefine degrees using `Set.ncard` to avoid `Fintype` and enable talking about degrees in infinite graphs. - Define `ENat` versions of `degree`/`minDegree`/`maxDegree` called `edegree`/`eminDegree`/`emaxDegree` respectively. - Remove `LocallyFinite` assumption from `IsRegularOfDegree`, and change it to use `edegree = k` instead of `degree = k` to retain the meaning of the case `k = 0`. --- The `e` prefix matches the existing `edist` and `ediam`. To make reviewing easier, this PR intentionally does not: - Add theorems about the new definitions - Reorder theorems to avoid `omit`s - Move theorems to a new `Degree.lean` file This is so that the diff shows the old/new versions side-by-side, and to avoid a bigger PR. Consequently a few proofs are a bit longer, but that'll be fixed after this PR by adding API lemmas for the new definitions (e.g. `edegree ≠ ⊤ → edegree = degree`). Regarding computability: If computability of degrees is useful, we can introduce a separate `findegree` in the future (similar to `neighborSet` vs `neighborFinset`), but I think degrees are a basic graph definition that should be defined for any `SimpleGraph`. As for theorems, such a `findegree` can use a lemma `findegree = degree` to access all the degree theorems, instead of duplicating everything to both versions. This PR was motivated by wanting to talk about infinite graphs with a finite max-degree. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics large-import 302/243 Archive/Wiedijk100Theorems/FriendshipGraphs.lean,Archive/Wiedijk100Theorems/Konigsberg.lean,Counterexamples/HeawoodUnitDistance.lean,Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/AdjMatrix.lean,Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Combinatorics/SimpleGraph/Circulant.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/DegreeSum.lean,Mathlib/Combinatorics/SimpleGraph/Extremal/Turan.lean,Mathlib/Combinatorics/SimpleGraph/Finite.lean,Mathlib/Combinatorics/SimpleGraph/FiveWheelLike.lean,Mathlib/Combinatorics/SimpleGraph/LapMatrix.lean,Mathlib/Combinatorics/SimpleGraph/Maps.lean,Mathlib/Combinatorics/SimpleGraph/Prod.lean,Mathlib/Combinatorics/SimpleGraph/StronglyRegular.lean,Mathlib/Combinatorics/SimpleGraph/Subgraph.lean,Mathlib/Combinatorics/SimpleGraph/Trails.lean,Mathlib/Data/Set/Card.lean,Mathlib/Data/Set/Insert.lean,Mathlib/Order/ConditionallyCompleteLattice/Finset.lean 21 1 ['github-actions'] adamtopaz
assignee:adamtopaz
1-41258
1 day ago
1-41258
1 day ago
5-37612
5 days
29241 yoh-tanimoto
author:yoh-tanimoto
feat(Analysis/InnerProductSpace/Orthogonal): add duplicates for `ClosedSubmodule` add duplicates of definitions and API's for `ClosedSubmodule` in an `InnerProductSpace`. motivation: when one considers a Hilbert space (`CompleteSpace`), it is more natural to consider `ClosedSubmodule`s. They form a complete lattice and satisfy `sup_orthogonal` #29243. - [x] depends on: #29230 for `Lattice` `CompleteLattice` 169/8 Mathlib/Analysis/Convex/Cone/Basic.lean,Mathlib/Analysis/Convex/Cone/Dual.lean,Mathlib/Analysis/InnerProductSpace/Orthogonal.lean,Mathlib/Topology/Algebra/Module/ClosedSubmodule.lean 4 9 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'sgouezel', 'yoh-tanimoto'] sgouezel
assignee:sgouezel
1-41108
1 day ago
1-47493
1 day ago
14-35423
14 days
33611 urkud
author:urkud
feat(ImplicitFunction): add a parametric version --- I'm not sure if the supporting linear algebra lemmas are in the form we want to see them in Mathlib. - [x] depends on: #33585 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis 191/0 Mathlib.lean,Mathlib/Analysis/Calculus/FDeriv/Prod.lean,Mathlib/Analysis/Calculus/ImplicitFunction/Parametric.lean,Mathlib/LinearAlgebra/Prod.lean 4 3 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] nobody
1-25681
1 day ago
1-25712
1 day ago
2-69029
2 days
33676 YuvalFilmus
author:YuvalFilmus
feat(Chebyshev/Orthogonality): Chebyshev T polynomials are orthogonal We prove that the Chebyshev T polynomials are orthogonal with respect to `1 / √ (1 - x ^ 2)`. Similarly, one could show that the Chebyshev U polynomials are orthogonal with respect to `√ (1 - x ^ 2)`, which I will do once this PR is approved. More generally, one defines an inner product space on the space of all real polynomials, where the inner product is as defined above. I will be happy to add this to the present or a future PR. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis 138/0 Mathlib.lean,Mathlib/Analysis/SpecialFunctions/Trigonometric/Chebyshev/Orthogonality.lean 2 2 ['github-actions', 'wwylele'] nobody
1-22965
1 day ago
1-67272
1 day ago
1-67309
1 day
33603 JovanGerb
author:JovanGerb
fix(translate): don't unfold aux lemmas, but translate them `to_additive` has some troublesome interactions with the module system, because it sometimes relies on unfolding theorems whose value is not exported. This PR fixes that by never unfolding these theorems, and instead creating their translation the first time they appear. This will help remove some instances of `import all` and instances of `proofsInPublic`. The only theorems that we still unfold are the auxiliary theorems created by `simp`. These have very small proofs, and these proofs are always exported, so it is fine to unfold them. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta 42/64 Mathlib/Lean/Name.lean,Mathlib/MeasureTheory/Function/LpSpace/DomAct/Continuous.lean,Mathlib/Tactic/Translate/Core.lean,MathlibTest/toAdditive.lean 4 2 ['github-actions', 'mathlib4-merge-conflict-bot'] nobody
1-22411
1 day ago
1-22430
1 day ago
2-75250
2 days
33239 JovanGerb
author:JovanGerb
feat(to_dual): linter for redundant uses of `to_dual`/`to_additive` This PR adds a linter that helps avoid unneccessary uses of `to_dual`/`to_additive`. With `to_dual self` it can sometimes be hard to tell if it's actually doing anything or not, so this will help with that. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 70/29 Mathlib/Algebra/BigOperators/Finsupp/Basic.lean,Mathlib/Algebra/Group/WithOne/Defs.lean,Mathlib/Analysis/Normed/Group/Continuity.lean,Mathlib/CategoryTheory/Types/Basic.lean,Mathlib/Order/Basic.lean,Mathlib/Order/Defs/PartialOrder.lean,Mathlib/Tactic/Translate/Core.lean,Mathlib/Tactic/Translate/ToAdditive.lean,Mathlib/Topology/Category/Profinite/Basic.lean,MathlibTest/DeprecateTo.lean,MathlibTest/Lint.lean,MathlibTest/ToDual.lean,MathlibTest/toAdditive.lean 13 5 ['github-actions', 'mathlib4-merge-conflict-bot', 'vihdzp'] bryangingechen
assignee:bryangingechen
1-22345
1 day ago
1-22363
1 day ago
14-20359
14 days
33665 JovanGerb
author:JovanGerb
fix(addRelatedDecl): support imported theorems in module This PR lets `elementwise`, `to_fun`, etc. work on theorems that are imported (and the body of the theorem is not available). These kinds of declarations have the axiom constant info, which was not supported before. As a bonus, I've also made it support unsafe theorems. I've removed the support for the auxiliary declaration being a `def`, because this is never used, and it wasn't clear to me what the expected behaviour there is exactly (e.g. should it be `reducible`?). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta 3/18 Mathlib/CategoryTheory/ConcreteCategory/Elementwise.lean,Mathlib/CategoryTheory/Elementwise.lean,Mathlib/Util/AddRelatedDecl.lean 3 1 ['github-actions'] nobody
1-17353
1 day ago
1-17353
1 day ago
2-2819
2 days
33347 AntoineChambert-Loir
author:AntoineChambert-Loir
feat(LinearAlgebra/Transvection/Basic): define dilatransvections Define `LinearEquiv.dilatransvections`. These are linear equivalences whose associated linear map is a transvection. This definition has the interest of being usable without any assumption on the base ring. Over a division ring, they correspond exactly to those linear equivalences `e` such that `e - LinearMap.id` has rank at most one. They (will) appear in Dieudonné's theorem that describes the generation of elements of the general linear group as products of several transvections and one additional dilatransvection. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
204/32 Mathlib/LinearAlgebra/Transvection.lean 1 n/a ['AntoineChambert-Loir', 'eric-wieser', 'github-actions'] nobody
1-16178
1 day ago
unknown
unknown
33666 JovanGerb
author:JovanGerb
chore(Tactic): remove duplicate instances This PR removes the two duplicate instances that were detected in `Mathlib.Tactic`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-meta maintainer-merge 30/57 Mathlib/Tactic/Linarith/Oracle/FourierMotzkin.lean,Mathlib/Tactic/NormNum/Basic.lean,Mathlib/Tactic/NormNum/Core.lean,Mathlib/Tactic/NormNum/GCD.lean,Mathlib/Tactic/NormNum/NatFactorial.lean,Mathlib/Tactic/NormNum/NatFib.lean,Mathlib/Tactic/NormNum/NatLog.lean,Mathlib/Tactic/NormNum/NatSqrt.lean,Mathlib/Tactic/NormNum/Pow.lean,Mathlib/Tactic/NormNum/Prime.lean,Mathlib/Tactic/NormNum/Result.lean,Mathlib/Tactic/ReduceModChar.lean 12 5 ['github-actions', 'grunweg', 'leanprover-radar'] nobody
1-14247
1 day ago
1-16602
1 day ago
2-1892
2 days
33709 wangying11123
author:wangying11123
feat(Analysis/Convex/Between):Add wbtw_of_sameRay_vsub_left add wbtw_of_sameRay_vsub_left Main additions `wbtw_of_sameRay_vsub_left` if the vectors from a point x to points y and z lie on the same ray, then y is weakly between x and z, or z is weakly between x and y. new-contributor 24/0 Mathlib/Analysis/Convex/Between.lean 1 2 ['github-actions'] nobody
1-7430
1 day ago
1-8218
1 day ago
1-8201
1 day
32134 mitchell-horner
author:mitchell-horner
feat(Topology/Real): theorems linking `IsGLB` with `BddBelow`, `Antitone`, `Tendsto _ atTop` Implement theorems linking `IsGLB` (`IsLUB`) with `BddBelow` (`BddAbove`), `Antitone` (`Monotone`), `Tendsto _ atTop` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology maintainer-merge large-import 124/69 Mathlib/Algebra/Order/Monoid/Canonical/Basic.lean,Mathlib/Analysis/Normed/Unbundled/SeminormFromConst.lean,Mathlib/Analysis/Normed/Unbundled/SpectralNorm.lean,Mathlib/Topology/Instances/NNReal/Lemmas.lean,Mathlib/Topology/Instances/Real/Lemmas.lean 5 24 ['YaelDillies', 'github-actions', 'mitchell-horner'] YaelDillies
assignee:YaelDillies
1-2520
1 day ago
1-2520
1 day ago
33-38818
33 days
33614 eric-wieser
author:eric-wieser
chore: tidy results around Module.Finite In particular this replaces many chains of `Module.finite_def` and `Submodule.fg_top` with `Module.Finite.iff_fg`. This also golfs some `FiniteDimensional` results in terms of their `Finite` counterparts, and adds `Submodule.fg_range` as a shorthand for a common case of `Submodule.fg_map`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 50/53 Mathlib/Algebra/Module/FinitePresentation.lean,Mathlib/Analysis/Normed/Module/FiniteDimension.lean,Mathlib/LinearAlgebra/FiniteDimensional/Basic.lean,Mathlib/LinearAlgebra/FiniteDimensional/Defs.lean,Mathlib/RingTheory/Finiteness/Basic.lean,Mathlib/RingTheory/FractionalIdeal/Basic.lean,Mathlib/RingTheory/IntegralClosure/Algebra/Basic.lean,Mathlib/RingTheory/IntegralClosure/IsIntegral/AlmostIntegral.lean,Mathlib/RingTheory/IntegralClosure/IsIntegralClosure/Basic.lean,Mathlib/RingTheory/LocalRing/Module.lean,Mathlib/RingTheory/Noetherian/Defs.lean,Mathlib/RingTheory/Smooth/Local.lean 12 1 ['github-actions'] nobody
1-2022
1 day ago
2-8868
2 days ago
2-68374
2 days
33604 xgenereux
author:xgenereux
feat(ValuationSubring): eq_top_iff + qol changes Given a `A : ValuationSubring K`, this PR adds the lemma `eq_top_iff : A = ⊤ ↔ ¬ A.valuation.IsNontrivial`. I have also made some small quality of life changes: 1. Added other forms of the basic rewrite lemmas with `Valuation.IsEquiv`: - `eq_zero` - `one_le_iff_one_le` - ~~`neq_one_iff_neq_one`~~ - `one_lt_iff_one_lt` - removed : `ne_zero` 2. Reorganized section following the `IsEquiv` namespace block in Valuation.Basic 3. Added lemmas `(h : v.IsEquiv v') : v.IsNontrivial ↔ v'.IsNontrivial` - `isNontrivial_of_isEquiv` - `isNontrivial_iff_isEquiv_isNontrivial` 4. Added simp tags 5. Added simp lemmas - `isNontrivial_valuationSubring_valuation_iff` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 69/38 Mathlib/NumberTheory/Padics/ValuativeRel.lean,Mathlib/RingTheory/Valuation/Basic.lean,Mathlib/RingTheory/Valuation/ValuationSubring.lean,Mathlib/RingTheory/Valuation/ValuativeRel/Basic.lean,Mathlib/Topology/Algebra/Valued/WithVal.lean 5 18 ['github-actions', 'mathlib4-merge-conflict-bot', 'vihdzp', 'xgenereux'] nobody
1-631
1 day ago
1-650
1 day ago
2-50470
2 days
33411 IlPreteRosso
author:IlPreteRosso
feat(Analysis/DiscreteConvolution): Discrete convolution API basics This is the first PR is a series of PRs towards the proposed API and ℓ1 Banach algebra. Defines discrete convolution of functions `f : M → E` and `g : M → E'` over a monoid `M` using a bilinear map `L : E →ₗ[S] E' →ₗ[S] F`: `(f ⋆[L] g) x = ∑' (a, b) : mulFiber x, L (f a) (g b)` where `abbrev mulFiber (x : M) : Set (M × M) := Set.mulAntidiagonal Set.univ Set.univ x` Declaration: AI tools used for debugging/facilitating peripheral commands (e.g. bash commands), docstrings, refactoring and condensing existing formalization. I welcome reviews on humanizing doctrings. Personally speaking, AI does a better job at writing those than what I can do. My brain isn't in the right condition to write human language after coding and debugging for hours and hours. The philosophy of me using AI tools is "hey gather information/spot patterns for me", other than "give me the answer". t-analysis new-contributor 489/0 Mathlib.lean,Mathlib/Analysis/DiscreteConvolution/Basic.lean 2 11 ['IlPreteRosso', 'github-actions', 'j-loreaux'] urkud
assignee:urkud
0-83126
23 hours ago
1-26124
1 day ago
8-20494
8 days
33417 themathqueen
author:themathqueen
feat: `{Continuous}Linear{Isometry}Equiv.conj{Continuous, Star}AlgEquiv` are "almost" injective ... "almost" meaning that they are colinear. I.e., `f.conj{Continuous, Star}AlgEquiv S = g.conj{Continuous, Star}AlgEquiv S` iff `f = α • g` for some (unitary) `α`. Also, the same for `Unitary.conjStarAlgAut`. All in one PR since they all have analogous proofs. --- - [x] depends on: #33301 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
243/4 Mathlib/Algebra/Central/End.lean,Mathlib/Algebra/Module/Equiv/Defs.lean,Mathlib/Algebra/Star/UnitaryStarAlgAut.lean,Mathlib/Analysis/InnerProductSpace/Adjoint.lean,Mathlib/Analysis/Normed/Operator/ContinuousAlgEquiv.lean,Mathlib/Topology/Algebra/Module/Equiv.lean 6 6 ['github-actions', 'mathlib4-dependent-issues-bot', 'themathqueen'] joelriou
assignee:joelriou
0-82976
23 hours ago
5-64368
5 days ago
5-64355
5 days
32757 AntoineChambert-Loir
author:AntoineChambert-Loir
feat(LinearAlgebra/Transvection): the determinant of a transvection is equal to 1. Prove that the determinant of a transvection is equal to 1 The proof goes by showing that the determinant of `LinearMap.transvection f v` is `1 + f v` (even if `f v` is nonzero). I first treat the case of a field, distinguishing whether `f v = 0` (so that we get a transvection) or not (so that we have a dilation). Then, by base change to the field of fractions, I can handle the case of a domain. Finally, the general case is treated by base change from the “universal case” where the base ring is the ring of polynomials in $$2n$$ indeterminates corresponding to the coefficients of $$f$$ and $$v$$. --- - [ ] depends on: #31138 - [ ] [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 255/0 Mathlib/LinearAlgebra/Determinant.lean,Mathlib/LinearAlgebra/Transvection.lean 2 n/a ['AntoineChambert-Loir', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] nobody
0-82026
22 hours ago
unknown
unknown
33718 erdOne
author:erdOne
feat(RingTheory): predicate for `QuasiFiniteAt` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 194/24 Mathlib/RingTheory/Etale/QuasiFinite.lean,Mathlib/RingTheory/LocalRing/ResidueField/Ideal.lean,Mathlib/RingTheory/Localization/AtPrime/Basic.lean,Mathlib/RingTheory/QuasiFinite/Basic.lean 4 1 ['github-actions'] nobody
0-78984
21 hours ago
0-78984
21 hours ago
0-79027
21 hours
33192 linesthatinterlace
author:linesthatinterlace
refactor(Data/List/Induction): improve definition of `reverseRecOn` This PR improves the definition of `List.reverseRecOn`. --- This improved approach aims to give identical behavior but give a somewhat nicer proof of `List.reverseRecOn_concat`. I do not believe it is a regression in terms of performance. The approach is inspired by `biDirectionalRec`, for which I have also tweaked the definitions and proofs, albeit in a much more minor way. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 32/27 Mathlib/Data/List/Induction.lean 1 6 ['github-actions', 'linesthatinterlace', 'vihdzp'] pechersky
assignee:pechersky
0-78089
21 hours ago
17-6553
17 days ago
17-6589
17 days
26377 Whysoserioushah
author:Whysoserioushah
feat(RingTheory/SimpleRing/TensorProduct): tensor product of a simple algebra and a central simple algebra is simple co-authored-by: @jjaassoonn --- t-ring-theory 203/0 Mathlib.lean,Mathlib/LinearAlgebra/Finsupp/LinearCombination.lean,Mathlib/RingTheory/SimpleRing/TensorProduct.lean,Mathlib/RingTheory/TwoSidedIdeal/Operations.lean 4 43 ['Ruben-VandeVelde', 'Whysoserioushah', 'eric-wieser', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot', 'vlad902'] kbuzzard
assignee:kbuzzard
0-72166
20 hours ago
4-66907
4 days ago
4-74492
4 days
32811 erdOne
author:erdOne
feat(RingTheory): predicate on satisfying Zariski's main theorem --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 179/0 Mathlib.lean,Mathlib/Algebra/Algebra/Subalgebra/Lattice.lean,Mathlib/RingTheory/Localization/Away/Basic.lean,Mathlib/RingTheory/ZariskisMainTheorem.lean 4 9 ['erdOne', 'github-actions', 'joelriou'] alreadydone
assignee:alreadydone
0-71388
19 hours ago
23-68542
23 days ago
26-55502
26 days
33698 artie2000
author:artie2000
feat(Algebra/Ring): characteristic of semireal ring * Prove that a semireal ring has characteristic zero * Prove that natural numbers are sums of squares --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
16/0 Mathlib/Algebra/Ring/Semireal/Defs.lean,Mathlib/Algebra/Ring/SumsOfSquares.lean 2 3 ['github-actions', 'vihdzp'] nobody
0-69362
19 hours ago
0-69433
19 hours ago
1-39387
1 day
32734 Vierkantor
author:Vierkantor
chore(Tactic): document remaining undocumented tactics Write documentation for the few tactics in Mathlib that have no documentation at all. After this PR and a few related ones are merged, every tactic defined in Mathlib should now have a docstring or a `@[tactic_alt]` attribute. ~~The documentation for `mem_tac` is pending a Zulip discussion: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Proj.20as.20a.20scheme.3A.20.60mem_tac.60.20works.20accidentally.3F/with/563193768~~ Zulip discussion now applies to the independent PR #33711. This PR can be merged before or after #33711 (or #33711 can be closed). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) documentation t-meta 28/0 Mathlib/Tactic/Conv.lean,Mathlib/Tactic/GCongr/Core.lean 2 3 ['Vierkantor', 'github-actions', 'mathlib4-merge-conflict-bot'] nobody
0-63957
17 hours ago
0-63997
17 hours ago
12-24532
12 days
33194 YuvalFilmus
author:YuvalFilmus
feat(LinearAlgebra/Lagrange): refactored proof of leadingCoeff_eq_sum The proof of `leadingCoeff_eq_sum` was slightly refactored. A subsequent PR will use the refactored parts to prove a formula for the iterated derivative of a polynomial at a point. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
22/22 Mathlib/LinearAlgebra/Lagrange.lean 1 6 ['Ruben-VandeVelde', 'YuvalFilmus', 'github-actions'] dagurtomas
assignee:dagurtomas
0-55840
15 hours ago
17-5242
17 days ago
17-5289
17 days
33679 DavidLedvinka
author:DavidLedvinka
feat(MeasureTheory): add formulas for the measures formed by a density with respect to counting or dirac measures. Like with most theorems that ultimately rely on application of dirac measures, there are primed versions for when the function (or set in other cases) is measurable, and unprimed versions for when `MeasurableSingletonClass` is assumed. t-measure-probability 21/0 Mathlib/MeasureTheory/Measure/WithDensity.lean 1 1 ['github-actions'] nobody
0-54432
15 hours ago
1-63788
1 day ago
1-63825
1 day
33688 Citronhat
author:Citronhat
feat(PMF): add expectation lemmas for Poisson PMF This PR adds some basic results about the Poisson distribution, its `PMF`, and its expectation. **New lemmas:** * `poissonPMF_apply` — an unfolding lemma for `poissonPMF`. * `poissonPMFReal_mul_eq_succ_mul` — the standard recursion identity for the Poisson mass function. * `poissonPMFReal_hasSum_nmul` — shows that `fun n ↦ poissonPMFReal r n * n` has sum `r`. * `poissonPMF_tsum_nmul` — the corresponding identity at the level of the `PMF`. * `poissonPMF_coe_tsum_nmul` — the same result after coercion to `ℝ`. Both `ℝ`-valued and `ℝ≥0∞`-valued formulations are included so that these results can be used conveniently in both Lebesgue and Bochner integration contexts. t-measure-probability new-contributor 21/0 Mathlib/Probability/Distributions/Poisson.lean 1 2 ['Citronhat', 'github-actions'] nobody
0-53152
14 hours ago
1-52943
1 day ago
1-52977
1 day
28546 Sfgangloff
author:Sfgangloff
feat(SymbolicDynamics): basic setup of Zd, full shift, cylinders, pat… This PR adds a **group-generic** foundation for symbolic dynamics over an arbitrary group `G`, together with convenient specializations for `ℤ` and `ℤ^d`. Summary of additions: - **Full shift and shift action** - `abbrev FullShift (A G) := G → A` (inherits product topology from the Π-type). - Right shift `shift g x` with convention `(shift g x) h = x (h * g)`. - **Cylinders and topology** - `cylinder U x : Set (G → A)` for finite `U : Finset G`. - Cylinders are open under `[DiscreteTopology A]`; with a finite alphabet they are also closed. - Equality with dependent products: `cylinder U x = Set.pi (↑U) (fun i => ({x i} : Set A))`, enabling use of the `Set.pi` API. - **Patterns, occurrences, and subshifts** - `Pattern A G` with finite `support : Finset G` and `data : support → A`. - `Pattern.occursIn p x g` (occurrence at translate `g`) and the expected shift law. - `forbids F` and `Subshift A G` (closed, shift-invariant subsets). - `FixedSupport A G U` with an equivalence to `(U → A)` to obtain finiteness. - **Language on finite shapes and counting** - `languageOn X U`, `languageCardOn X U`, and `patternCountOn Y U`. - **Entropy along a shape sequence** - `limsupAtTop` (as an `sInf` of eventual upper bounds). - `entropyAlong X F hF := limsup (log (patternCountOn X (F n) + 1) / |F n|)` for any nonempty finite shapes `F : ℕ → Finset G` (the `+ 1` avoids `log 0`). - **Specializations** - `IntShapes`: segments `[-n,n]` on `Multiplicative ℤ`, with `entropy_Z`. - `ZdShapes`: boxes `[-n,n]^d` on `ℤ^d` (as functions `Fin d → ℤ`), with `entropy_Zd`. Mathematical remarks: - The API is **shape-parametric**: entropy is defined along user-provided finite shapes. - On **amenable** groups, using a **Følner** sequence yields a canonical value (Ornstein–Weiss). This PR does not assume amenability; the family of shapes is an explicit input. Motivation: Provide a clean, reusable base for symbolic dynamics on groups in mathlib. Future work: - Add a Følner predicate and prove shape-independence / limit existence on amenable groups. - Expand the `ℤ`/`ℤ^d` toolkit (alternative shapes, mixing, factors). - Develop 1D theory and, longer-term, multidimensional SFT results (e.g. along the lines of Hochman–Meyerovitch). t-dynamics new-contributor 756/0 Mathlib.lean,Mathlib/Dynamics/SymbolicDynamics/Basic.lean,Mathlib/Tactic/Translate/ToAdditive.lean 3 156 ['Sfgangloff', 'eric-wieser', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot', 'sgouezel'] sgouezel
assignee:sgouezel
0-52560
14 hours ago
1-24014
1 day ago
87-32910
87 days
33700 vihdzp
author:vihdzp
feat: dense orders have elements lying between two finite sets Used in the CGT repo, and will be used not too long in the future to show dense orders are η₀-sets. Co-authored-by: Kenny Lau --- See [Zulip](https://leanprover.zulipchat.com/#narrow/channel/217875-Is-there-code-for-X.3F/topic/.60exists_between.60.20for.20finite.20sets/near/526965677). Is the import increase a problem? If so, would a new file for these theorems be desirable? Or where else should they go? [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-order large-import 30/0 Mathlib/Data/Finset/Max.lean 1 1 ['github-actions'] nobody
0-52429
14 hours ago
1-32808
1 day ago
1-32841
1 day
33724 alreadydone
author:alreadydone
chore(Algebra): deprecate `DistribMulAction.toAddMonoidHom` which is simply a specialized version of `DistribSMul.toAddMonoidHom`. `MulDistribMulAction.toMonoidHom` has to be kept, since there is no `MulDistribSMul` yet. also deprecates `AddMonoidHom.smulLeft` (same situation) --- - [x] depends on: #33721 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
111/99 Mathlib/Algebra/Algebra/Hom.lean,Mathlib/Algebra/Algebra/Tower.lean,Mathlib/Algebra/BigOperators/Finprod.lean,Mathlib/Algebra/Category/ModuleCat/Tannaka.lean,Mathlib/Algebra/DirectSum/Algebra.lean,Mathlib/Algebra/GroupWithZero/Action/Basic.lean,Mathlib/Algebra/GroupWithZero/Action/Defs.lean,Mathlib/Algebra/GroupWithZero/Action/End.lean,Mathlib/Algebra/Module/Basic.lean,Mathlib/Algebra/Module/Equiv/Basic.lean,Mathlib/Algebra/Module/Hom.lean,Mathlib/Algebra/Module/LinearMap/Defs.lean,Mathlib/Algebra/Module/LinearMap/End.lean,Mathlib/Algebra/Module/Rat.lean,Mathlib/Algebra/Module/Submodule/Invariant.lean,Mathlib/Algebra/Module/Submodule/Pointwise.lean,Mathlib/Algebra/Module/Torsion/Basic.lean,Mathlib/Algebra/Polynomial/HasseDeriv.lean,Mathlib/Algebra/QuadraticAlgebra/NormDeterminant.lean,Mathlib/Algebra/Ring/Action/Basic.lean,Mathlib/Analysis/SpecialFunctions/Gamma/BohrMollerup.lean,Mathlib/LinearAlgebra/AffineSpace/Pointwise.lean,Mathlib/LinearAlgebra/BilinearMap.lean,Mathlib/LinearAlgebra/Matrix/ToLin.lean,Mathlib/LinearAlgebra/TensorProduct/Basic.lean,Mathlib/LinearAlgebra/TensorProduct/Graded/External.lean,Mathlib/RingTheory/DiscreteValuationRing/TFAE.lean,Mathlib/RingTheory/FractionalIdeal/Basic.lean,Mathlib/RingTheory/IntegralClosure/Algebra/Basic.lean,Mathlib/RingTheory/Jacobson/Ideal.lean,Mathlib/RingTheory/Morita/Matrix.lean,Mathlib/RingTheory/Regular/IsSMulRegular.lean,Mathlib/Topology/Algebra/InfiniteSum/Module.lean,Mathlib/Topology/Algebra/Ring/Real.lean,Mathlib/Topology/Algebra/UniformMulAction.lean 35 2 ['github-actions', 'mathlib4-dependent-issues-bot'] nobody
0-52232
14 hours ago
0-52232
14 hours ago
0-52206
14 hours
33288 vihdzp
author:vihdzp
chore(Combinatorics/SimpleGraph/Paths): review API This PR does the following: - Add `grind` annotations. - Rename theorems `X_isY` to the more idiomatic `isY_X`. - Remove many redundant namespaces. - Golf accordingly. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 154/122 Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean,Mathlib/Combinatorics/SimpleGraph/Matching.lean,Mathlib/Combinatorics/SimpleGraph/Metric.lean,Mathlib/Combinatorics/SimpleGraph/Paths.lean,Mathlib/Combinatorics/SimpleGraph/Walks/Maps.lean 6 2 ['github-actions', 'mathlib4-merge-conflict-bot'] nobody
0-51327
14 hours ago
0-51347
14 hours ago
4-1868
4 days
33185 alreadydone
author:alreadydone
feat(Algebra): MulAction/SMulWithZero by Nat/Int --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
22/2 Mathlib/Algebra/Group/Basic.lean,Mathlib/Algebra/Group/Defs.lean,Mathlib/Algebra/Module/NatInt.lean 3 3 ['alreadydone', 'github-actions', 'leanprover-radar'] nobody
0-48755
13 hours ago
0-50722
14 hours ago
0-56489
15 hours
33699 artie2000
author:artie2000
chore(Algebra/Ring): semireal definition lemmas * Add converse to `IsSemireal.not_isSumSq_neg_one ` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
9/2 Mathlib/Algebra/Ring/Semireal/Defs.lean 1 4 ['artie2000', 'github-actions', 'vihdzp'] nobody
0-47037
13 hours ago
1-40094
1 day ago
1-40128
1 day
33336 fbarroero
author:fbarroero
feat(NumberTheory/MahlerMeasure): Kronecker's Theorem for the Mahler Measure This PR adds Kronecker's Theorem for the Mahler Measure, which characterizes integer polynomials with Mahler measure equal to 1. The key mathematical contribution is proving that such polynomials have all their nonzero complex roots as roots of unity, and consequently must be divisible by cyclotomic polynomials. Main result ``` Polynomial.pow_eq_one_of_mahlerMeasure_eq_one {p : ℤ[X]} (h : (map (castRingHom ℂ) p).mahlerMeasure = 1) {z : ℂ} (hz₀ : z ≠ 0) (hz : z ∈ p.aroots ℂ) : ∃ n, 0 < n ∧ z ^ n = 1 ``` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 128/9 Mathlib/Algebra/Order/BigOperators/Ring/Multiset.lean,Mathlib/NumberTheory/MahlerMeasure.lean 2 11 ['copilot-pull-request-reviewer', 'github-actions', 'mathlib4-merge-conflict-bot'] tb65536
assignee:tb65536
0-45380
12 hours ago
4-71466
4 days ago
7-76218
7 days
33633 mcdoll
author:mcdoll
chore(Analysis/Fourier): split type class, add continuity one The combined type-class `FourierModule` causes problems when using `fourier_add` since it needs a `Semiring R`, which does not appear in the statement. Therefore, we split `FourierModule` into `FourierAdd` and `FourierSMul` (similar to the case of `LineDeriv`. Moreover, we add the class `ContinuousFourier` which states that the Fourier transform is continuous. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis large-import 195/77 Mathlib/Analysis/Distribution/FourierSchwartz.lean,Mathlib/Analysis/Distribution/TemperedDistribution.lean,Mathlib/Analysis/Fourier/LpSpace.lean,Mathlib/Analysis/Fourier/Notation.lean 4 1 ['github-actions'] nobody
0-44445
12 hours ago
0-44514
12 hours ago
2-50778
2 days
28708 sjh227
author:sjh227
feat(LinearAlgebra): define row- and column-stochastic matrices This PR defines row- and column-stochastic matrices, and relates them to doubly stochastic matrices (which are already in mathlib). --- new-contributor t-data 255/6 Mathlib.lean,Mathlib/Algebra/Group/Submonoid/Defs.lean,Mathlib/Analysis/Convex/DoublyStochasticMatrix.lean,Mathlib/LinearAlgebra/Matrix/Stochastic.lean 4 29 ['dupuisf', 'github-actions', 'j-loreaux', 'mathlib4-merge-conflict-bot', 'sjh227'] pechersky
assignee:pechersky
0-43909
12 hours ago
3-56160
3 days ago
4-47755
4 days
31854 erdOne
author:erdOne
chore(AlgebraicGeometry): API for `𝒪ₓ`-modules --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebraic-geometry 430/18 Mathlib/Algebra/Category/ModuleCat/ChangeOfRings.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Colimits.lean,Mathlib/Algebra/Category/ModuleCat/Presheaf/Limits.lean,Mathlib/Algebra/Category/ModuleCat/Sheaf/Colimits.lean,Mathlib/Algebra/Category/ModuleCat/Sheaf/PullbackContinuous.lean,Mathlib/Algebra/Category/ModuleCat/Sheaf/PushforwardContinuous.lean,Mathlib/AlgebraicGeometry/Modules/Sheaf.lean,Mathlib/AlgebraicGeometry/OpenImmersion.lean 8 4 ['erdOne', 'github-actions', 'joelriou', 'mathlib4-merge-conflict-bot'] dagurtomas
assignee:dagurtomas
0-43907
12 hours ago
4-31672
4 days ago
5-14936
5 days
32481 ADedecker
author:ADedecker
feat: add `PolynormableSpace.banach_steinhaus` --- - [ ] depends on: #32480 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) blocked-by-other-PR t-analysis 121/24 Mathlib/Analysis/LocallyConvex/AbsConvexOpen.lean,Mathlib/Analysis/LocallyConvex/Barrelled.lean,Mathlib/Analysis/LocallyConvex/WithSeminorms.lean,Mathlib/Analysis/Normed/Operator/BanachSteinhaus.lean 4 2 ['github-actions', 'mathlib4-dependent-issues-bot'] nobody
33-68973
1 month ago
33-71044
1 month ago
0-1302
21 minutes
33312 YuvalFilmus
author:YuvalFilmus
feat(Polynomial/Chebyshev): formulas for iterated derivatives of T and U at 1 The main results are `iterate_derivative_T_eval_one` and `iterate_derivative_U_eval_one`. These are derived using recurrences which for at every point, and in particular, `iterate_derivative_T_eval_zero` and `iterate_derivative_U_eval_zero` gives the recurrences at zero. In principle, by combining with #33311, one can compute the explicit formula for the derivative at zero. A subsequent PR will derive consequences for these polynomials over the reals (these should work for every field). The file is getting rather long — not sure what to do about it. --- - [ ] depends on: #33283 - [ ] depends on: #33306 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) 110/0 Mathlib/RingTheory/Polynomial/Chebyshev.lean 1 3 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] RemyDegenne
assignee:RemyDegenne
0-43905
12 hours ago
0-67726
18 hours ago
0-69196
19 hours
33372 kex-y
author:kex-y
feat(Probability): Countable infimum of stopping times is a stopping time --- - [x] depends on: #33371 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability brownian 83/0 Mathlib/Probability/Process/Stopping.lean 1 3 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] RemyDegenne
assignee:RemyDegenne
0-43903
12 hours ago
3-83362
3 days ago
4-2825
4 days
33436 astrainfinita
author:astrainfinita
feat: lemmas about `(Add)MonoidAlgebra.mapRangeRingHom` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
21/0 Mathlib/Algebra/MonoidAlgebra/Basic.lean,Mathlib/Algebra/MonoidAlgebra/MapDomain.lean 2 2 ['github-actions', 'mathlib4-merge-conflict-bot'] chrisflav
assignee:chrisflav
0-43902
12 hours ago
3-58848
3 days ago
6-49124
6 days
33493 michelsol
author:michelsol
feat(RingTheory/Polynomial): An explicit formula for the Chebyshev polynomials of the first kind Adds the following explicit formula on the Chebyshev polynomial of the first kind of order n. ${ T_{n}(x)\ =\ \sum \limits _{k=0}^{\lfloor {\frac {n}{2}}\rfloor } {\binom {n}{2k}} \left(\ X^{2}-1\ \right)^{k}\ X^{n-2k}}$ This explicit formula can be found [here](https://en.wikipedia.org/wiki/Chebyshev_polynomials#Explicit_expressions). There is a proof using complex numbers but it only works if the ring R = ℂ. The proof here is by induction and works in a commutative ring R. Mathlib seems to extend the definition of Chebyshev polynomials for $n \in \mathbb{Z}$ but this would make the formula more cumbersome with `n.natAbs` in place of `n`'s, so I expressed it on `n : ℕ` directly. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-ring-theory 51/1 Mathlib/RingTheory/Polynomial/Chebyshev.lean 1 7 ['YuvalFilmus', 'erdOne', 'github-actions', 'metakunt', 'michelsol'] nobody
3-65854
3 days ago
3-65855
3 days ago
4-58721
4 days
33532 vihdzp
author:vihdzp
feat(RingTheory/Valuation/ValuativeRel): introduce `=ᵥ` relation Of course, the characterizing property is that for any compatible valuation, `x =ᵥ y` is equivalent to `v x = v y`. --- I haven't yet introduced too much API. I'll be using this on the CGT repo in order to define a `ValuativeRel Surreal` instance compatible with `ArchimedeanClass.mk`. If there's any API I'm missing, I'll upstream it in a subsequent PR. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 67/14 Mathlib/RingTheory/Valuation/ValuativeRel/Basic.lean 1 2 ['github-actions', 'vihdzp'] erdOne
assignee:erdOne
0-43900
12 hours ago
4-44888
4 days ago
4-44872
4 days
33535 erdOne
author:erdOne
feat(Algebra/Category): `Under.pushout` preserves finite limits for flat homomorphisms --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
159/5 Mathlib.lean,Mathlib/Algebra/Category/AlgCat/Basic.lean,Mathlib/Algebra/Category/AlgCat/Limits.lean,Mathlib/Algebra/Category/CommAlgCat/BaseChange.lean,Mathlib/Algebra/Category/CommAlgCat/Basic.lean,Mathlib/Algebra/Category/ModuleCat/ChangeOfRings.lean,Mathlib/Algebra/Category/ModuleCat/Limits.lean,Mathlib/Algebra/Category/Ring/Flat.lean 8 1 ['github-actions'] eric-wieser
assignee:eric-wieser
0-43899
12 hours ago
4-33970
4 days ago
4-34008
4 days
33539 BryceT233
author:BryceT233
feat(RingTheory/MvPolynomial): powers of ideal of variables proved some helper results for powers of the ideal of variables in `MvPolynomial` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-ring-theory 98/1 Mathlib/RingTheory/MvPolynomial/Ideal.lean 1 8 ['BryceT233', 'erdOne', 'github-actions', 'vihdzp'] erdOne
assignee:erdOne
0-43898
12 hours ago
4-19311
4 days ago
4-19343
4 days
33544 YaelDillies
author:YaelDillies
chore(LinearAlgebra): make one more argument implicit in `ker_toSpanSingleton` `M` can be inferred from `x : M` which can be inferred from `h : x ≠ 0`. Similarly for `ker_toSpanSingleton_eq_bot_iff`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
5/5 Mathlib/LinearAlgebra/Span/Basic.lean,Mathlib/RingTheory/SimpleModule/Basic.lean,Mathlib/RingTheory/WittVector/Isocrystal.lean,Mathlib/Topology/Algebra/Module/FiniteDimension.lean 4 2 ['artie2000', 'github-actions'] joelriou
assignee:joelriou
0-43897
12 hours ago
4-12309
4 days ago
4-12291
4 days
33555 erdOne
author:erdOne
feat(RingTheory): standard smooth = etale over mvpolynomial --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) large-import 79/2 Mathlib/Algebra/MvPolynomial/Equiv.lean,Mathlib/Algebra/MvPolynomial/PDeriv.lean,Mathlib/RingTheory/RingHom/StandardSmooth.lean 3 2 ['erdOne', 'github-actions'] robin-carlier
assignee:robin-carlier
0-43895
12 hours ago
3-64985
3 days ago
3-65019
3 days
33562 kim-em
author:kim-em
feat(ConvexSpace): complete `proof_wanted` statements This PR proves the three `proof_wanted` statements for `convexComboPair`: - `convexComboPair_zero`: weight 0 on first point gives the second point - `convexComboPair_one`: weight 1 on first point gives the first point - `convexComboPair_same`: any convex combo of a point with itself is that point Also adds supporting lemmas: - `StdSimplex.ext`: extensionality lemma for `StdSimplex` - `StdSimplex.mk_single`: simp lemma for constructor applied to single - `@[simp]` attribute on `ConvexSpace.single` 🤖 Prepared with Claude Code t-algebra
label:t-algebra$
24/7 Mathlib/LinearAlgebra/ConvexSpace.lean 1 3 ['github-actions', 'kim-em', 'themathqueen'] riccardobrasca
assignee:riccardobrasca
0-43894
12 hours ago
3-47223
3 days ago
3-47263
3 days
33697 artie2000
author:artie2000
feat(FieldTheory): real closed field * Define real closed fields * Prove some very basic properties --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra
label:t-algebra$
117/0 Mathlib.lean,Mathlib/FieldTheory/IsRealClosed/Basic.lean 2 31 ['artie2000', 'github-actions', 'vihdzp'] nobody
0-42419
11 hours ago
0-46467
12 hours ago
1-16057
1 day
30640 SnirBroshi
author:SnirBroshi
feat(Combinatorics/SimpleGraph/Acyclic): acyclic and bridge theorems --- - [x] depends on: #30542 - [x] depends on: #30570 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 69/69 Mathlib/Combinatorics/SimpleGraph/Acyclic.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/Connected.lean 2 4 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] b-mehta
assignee:b-mehta
0-40614
11 hours ago
0-40634
11 hours ago
30-2311
30 days
33355 0xTerencePrime
author:0xTerencePrime
feat(Combinatorics/SimpleGraph/Connectivity): define vertex connectivity 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`: vertices remain reachable after removing strictly fewer than `k` other vertices. - `SimpleGraph.IsVertexConnected`: a graph is `k`-vertex-connected if its order is strictly greater than `k` and any two distinct vertices are `k`-vertex-reachable. Includes basic characterizations for $k=0$ and $k=1$, along with monotonicity lemmas (`anti` and `mono`). t-combinatorics new-contributor 160/0 Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/VertexConnectivity.lean,Mathlib/Combinatorics/SimpleGraph/IsolateVerts.lean 3 87 ['0xTerencePrime', 'SnirBroshi', 'github-actions', 'vihdzp'] nobody
0-72011
20 hours ago
11-3330
11 days ago
11-3362
11 days
32617 erdOne
author:erdOne
feat(RingTheory): field extension over perfect fields are smooth --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-ring-theory 150/18 Mathlib.lean,Mathlib/FieldTheory/IntermediateField/Adjoin/Algebra.lean,Mathlib/FieldTheory/IntermediateField/Adjoin/Defs.lean,Mathlib/FieldTheory/SeparableClosure.lean,Mathlib/FieldTheory/SeparablyGenerated.lean,Mathlib/RingTheory/EssentialFiniteness.lean,Mathlib/RingTheory/Smooth/Field.lean 7 6 ['chrisflav', 'erdOne', 'github-actions', 'robin-carlier'] chrisflav
assignee:chrisflav
0-38045
10 hours ago
0-38106
10 hours ago
10-73281
10 days
29960 yonggyuchoimath
author:yonggyuchoimath
feat(Algebra/Category/Ring): equalizers of pushout maps of tensor product inclusions This PR defines a ring map `S →ₗ[R] S ⊗[R] S : s ↦ (s ⊗ₜ[R] 1) - (1 ⊗ₜ[R] s)` for an `R`-algebra `S`, and show that its kernel is exactly (the image of) `R` if `S` is faithfully flat over `R`. Changes: * `TensorProduct.AlgebraTensorModule.distribBaseChange`: Origianlly takes `M` and `N`, where `M` is an `R`-module with an additional instance `IsScalarTower R A M`. This is unnecessary, so I changed the `M` and `N` into `N` and `Q`, now both of which are merely modules over `R`. Main results : * Add compatibility of `Algebra.TensorProduct.includeLeft` (or `Algebra.TensorProduct.includeRight`) with `TensorProduct.AlgebraTensorModule.distribBaseChange` and `LinearMap.lTensor` * Define `Algebra.TensorProduct.includeLeftSubRight`, which is the `R`-linear map `S →ₗ[R] S ⊗[R] S` sending `s : S` to `(s ⊗ₜ[R] 1) - (1 ⊗ₜ[R] s)`. * `Algebra.isEffective_of_faithfullyFlat`: the pair `algebraMap : R → S` and `includeLeftSubRight R S : S → S ⊗[R] S` is exact if `S` is a faithfully flat `R`-algebra. --- - [x] depends on: #30806 new-contributor t-ring-theory 214/1 Mathlib.lean,Mathlib/LinearAlgebra/TensorProduct/Tower.lean,Mathlib/RingTheory/TensorProduct/IncludeLeftSubRight.lean,Mathlib/RingTheory/TensorProduct/Maps.lean 4 20 ['erdOne', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'yonggyuchoimath'] PatrickMassot and erdOne
assignee:PatrickMassot assignee:erdOne
0-36773
10 hours ago
0-36773
10 hours ago
54-69317
54 days
33636 mcdoll
author:mcdoll
feat(Analysis/Distribution): the Laplacian on Schwartz functions We introduce a notation type-class for the Laplacian, change the definition of `InnerProductSpace.laplacian` to `Laplacian.laplacian` and define the Laplacian using the sum of second derivatives on Schwartz functions. We define an abstract Laplacian for any space with `LineDeriv` in order to avoid duplication for other function spaces (in particular, this will be reused for the tempered distribution Laplacian). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis 197/12 Mathlib.lean,Mathlib/Analysis/Distribution/DerivNotation.lean,Mathlib/Analysis/Distribution/Laplacian.lean,Mathlib/Analysis/Distribution/SchwartzSpace.lean,Mathlib/Analysis/InnerProductSpace/Harmonic/Basic.lean,Mathlib/Analysis/InnerProductSpace/Laplacian.lean 6 3 ['github-actions', 'mcdoll'] nobody
0-33214
9 hours ago
2-49544
2 days ago
2-49587
2 days
33033 kim-em
author:kim-em
feat(Tactic/Choose): add type annotation support This PR adds support for type annotations in the `choose` tactic, similar to how `intro` supports them. This allows writing: ```lean choose (n : ℕ) (hn : n > 0) using h ``` instead of just `choose n hn using h`. The type annotation is checked against the actual type from the existential, and an error is raised if they don't match. This is useful for pedagogical purposes and for catching mistakes early. Requested on Zulip: https://leanprover.zulipchat.com/#narrow/channel/187764-Lean-for-teaching/topic/adding.20type.20annotation.20to.20.60choose.60/near/564323626 🤖 Prepared with Claude Code t-meta 163/22 Mathlib/Tactic/Choose.lean,MathlibTest/choose.lean 2 20 ['AlexKontorovich', 'eric-wieser', 'fpvandoorn', 'github-actions', 'kim-em'] joneugster
assignee:joneugster
1-12278
1 day ago
19-54709
19 days ago
20-39107
20 days
33726 alreadydone
author:alreadydone
feat(Analysis): (complex) polynomials as branched coverings originally proposed by @urkud in #33425 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology t-analysis 124/4 Mathlib/Algebra/Polynomial/Roots.lean,Mathlib/Analysis/Complex/CoveringMap.lean,Mathlib/Topology/Algebra/Polynomial.lean,Mathlib/Topology/Covering/Basic.lean 4 2 ['alreadydone', 'github-actions'] nobody
0-13178
3 hours ago
0-51828
14 hours ago
0-51871
14 hours
33704 kebekus
author:kebekus
feat: behavior under addition of the characteristic function of Value Distribution Theory Combine results of PR #32311 and #31556 to establish the behavior under addition of the characteristic function of Value Distribution Theory. This material is used in [Project VD](https://github.com/kebekus/ProjectVD), formalizing Value Distribution Theory for meromorphic functions on the complex plane. The formula established here is part of a larger package discussing the behavior of the Nenvanlinna height under algebraic manipulations of the functions. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis 61/2 Mathlib/Analysis/Complex/ValueDistribution/CharacteristicFunction.lean 1 11 ['github-actions', 'j-loreaux', 'kebekus'] nobody
0-12400
3 hours ago
1-17454
1 day ago
1-18392
1 day
33504 ldct
author:ldct
feat: Add lemmas for DihedralGroup.fintypeHelper Using `fin_cases` to reason about `DihedralGroup` elements exposes the internal `fintypeHelper` instances, which has no exported API ``` example (g : DihedralGroup 3) : (g^6 = 1) := by fin_cases g <;> dsimp -- 6 goals case «0» ⊢ DihedralGroup.fintypeHelper✝ (Sum.inl 0) ^ 6 = 1 ... ``` this PR adds simp lemma that convert them to constructors, which do have API ``` 6 goals case «0» ⊢ 1 ^ 6 = 1 case «1» ⊢ DihedralGroup.r 1 ^ 6 = 1 case «2» ⊢ DihedralGroup.r 2 ^ 6 = 1 ``` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-group-theory 8/0 Mathlib/GroupTheory/SpecificGroups/Dihedral.lean 1 1 ['github-actions', 'tb65536'] tb65536
assignee:tb65536
0-43900
12 hours ago
5-29684
5 days ago
5-29722
5 days
33714 idontgetoutmuch
author:idontgetoutmuch
Riemannian metrics exist II Supersedes https://github.com/leanprover-community/mathlib4/pull/33519 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-differential-geometry new-contributor 1269/0 Mathlib.lean,Mathlib/Geometry/Manifold/ExistsRiemannianMetricTangentSpace.lean,Mathlib/Geometry/Manifold/PartitionOfUnity.lean 3 1 ['github-actions'] nobody
0-11802
3 hours ago
0-11802
3 hours ago
0-84085
23 hours
33744 bilichboris
author:bilichboris
feat(RingTheory): Class Group of a Unique Factorization Domain is trivial Add a theorem that the class group of a unique factorization domain is trivial. Together with the PR relating `ClassGroup` to `PicardGroup`, this will close a TODO in `Mathlib.RingTheory.PicardGroup` that the Picard Group of a UFD is trivial. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-ring-theory 712/0 Mathlib.lean,Mathlib/RingTheory/UniqueFactorizationDomain/ClassGroup.lean 2 3 ['github-actions', 'jcommelin'] nobody
0-9484
2 hours ago
0-14702
4 hours ago
0-14743
4 hours
27599 mitchell-horner
author:mitchell-horner
feat(Combinatorics/SimpleGraph): define `CompleteEquipartiteSubgraph` Define the complete equipartite subgraphs in `r` parts each of size `t` in `G` as the `r` subsets of vertices each of size `t` such that vertices in distinct subsets are adjacent. In this case `Nonempty (G.CompleteEquipartiteSubgraph r t)` is equivalent to `completeEquipartiteGraph r t ⊑ G`, that is, finding `r` subsets of vertices each of size `t` in `G` such that vertices in distinct subsets are adjacent is equivalent to finding an injective homomorphism from `completeEquipartiteGraph r t` to `G`. --- - [x] depends on: #27597 - [x] depends on: #30287 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics 163/7 Mathlib/Combinatorics/SimpleGraph/CompleteMultipartite.lean 1 33 ['YaelDillies', 'b-mehta', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'mitchell-horner'] YaelDillies
assignee:YaelDillies
0-73217
20 hours ago
1-43358
1 day ago
72-6170
72 days
33751 mcdoll
author:mcdoll
feat(Analysis/FourierSchwartz): self-adjointness for the inverse Fourier transform This follows trivially from the facts about the Fourier transform and the inversion formula. In passing, we fix a doc-string. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis 20/1 Mathlib/Analysis/Distribution/FourierSchwartz.lean 1 1 ['github-actions'] nobody
0-4578
1 hour ago
0-4578
1 hour ago
0-4620
1 hour
33749 plp127
author:plp127
feat: `NNRat` is countable We provide an `Encodable NNRat` instance. As a consequence we also get the instance `Countable NNRat`. See also [Zulip](https://leanprover.zulipchat.com/#narrow/channel/113489-new-members/topic/NNRat.20not.20countable.3F/near/566916284) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-data 6/0 Mathlib/Data/Rat/Encodable.lean 1 4 ['eric-wieser', 'github-actions', 'grunweg', 'leanprover-radar'] nobody
0-4794
1 hour ago
0-4851
1 hour ago
0-5603
1 hour
30736 alreadydone
author:alreadydone
feat(RingTheory): Picard group of a domain is isomorphic to ClassGroup --- - [x] depends on: #30657 - [x] depends on: #33095 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) large-import t-ring-theory 310/79 Mathlib/RingTheory/PicardGroup.lean 1 32 ['alreadydone', 'erdOne', 'github-actions', 'jcommelin', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'tb65536'] mariainesdff
assignee:mariainesdff
0-2005
33 minutes ago
3-52363
3 days ago
46-81985
46 days
30799 YaelDillies
author:YaelDillies
refactor: unify the two versions of `pow_eq_one_iff` One version is about torsion-free monoids, the other one about linearly ordered monoids. I argue that all linearly ordered monoids of interest are torsion-free, and therefore the correct lemma to keep is the former. [Zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Should.20linear.20ordered.20comm.20monoids.20with.20zero.20be.20torsion-free) --- - [x] depends on: #30680 - [x] depends on: #31024 - [x] depends on: #31025 - [x] depends on: #31026 - [x] depends on: #31027 - [x] depends on: #31283 - [ ] depends on: #31749 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) blocked-by-other-PR t-algebra large-import file-removed
label:t-algebra$
265/358 Counterexamples.lean,Counterexamples/LinearOrderWithPosMulPosEqZero.lean,Mathlib/Algebra/Group/Torsion.lean,Mathlib/Algebra/GroupWithZero/Torsion.lean,Mathlib/Algebra/Order/AddGroupWithTop.lean,Mathlib/Algebra/Order/Field/Canonical.lean,Mathlib/Algebra/Order/GroupWithZero/Canonical.lean,Mathlib/Algebra/Order/Monoid/Unbundled/Pow.lean,Mathlib/Algebra/Order/Nonneg/Ring.lean,Mathlib/Algebra/Order/PUnit.lean,Mathlib/Algebra/Order/Ring/Archimedean.lean,Mathlib/Algebra/Order/Ring/Basic.lean,Mathlib/Algebra/Order/Ring/Nat.lean,Mathlib/Algebra/Order/Ring/StandardPart.lean,Mathlib/Algebra/Ring/NonZeroDivisors.lean,Mathlib/Algebra/Ring/Torsion.lean,Mathlib/Data/ENNReal/Basic.lean,Mathlib/Data/ENNReal/Real.lean,Mathlib/Data/EReal/Operations.lean,Mathlib/Data/Nat/PartENat.lean,Mathlib/Data/Nat/Prime/Pow.lean,Mathlib/FieldTheory/Finite/GaloisField.lean,Mathlib/LinearAlgebra/Dimension/Finite.lean,Mathlib/MeasureTheory/Function/ConditionalExpectation/Real.lean,Mathlib/MeasureTheory/Function/ConvergenceInMeasure.lean,Mathlib/MeasureTheory/Integral/Bochner/Basic.lean,Mathlib/MeasureTheory/Integral/Bochner/Set.lean,Mathlib/MeasureTheory/Integral/Lebesgue/Basic.lean,Mathlib/MeasureTheory/Measure/Decomposition/Exhaustion.lean,Mathlib/MeasureTheory/Measure/Doubling.lean,Mathlib/MeasureTheory/Measure/EverywherePos.lean,Mathlib/MeasureTheory/Measure/LevyProkhorovMetric.lean,Mathlib/MeasureTheory/Measure/TightNormed.lean,Mathlib/MeasureTheory/OuterMeasure/BorelCantelli.lean,Mathlib/NumberTheory/ArithmeticFunction/Moebius.lean,Mathlib/RingTheory/HahnSeries/Valuation.lean,Mathlib/RingTheory/Valuation/Archimedean.lean,Mathlib/RingTheory/Valuation/Basic.lean,Mathlib/RingTheory/Valuation/ValuationRing.lean,Mathlib/RingTheory/Valuation/ValuativeRel/Basic.lean,Mathlib/RingTheory/ZMod/UnitsCyclic.lean,Mathlib/SetTheory/Cardinal/Aleph.lean,Mathlib/SetTheory/Cardinal/Order.lean,Mathlib/Topology/EMetricSpace/BoundedVariation.lean,Mathlib/Topology/Instances/AddCircle/Defs.lean,Mathlib/Topology/MetricSpace/HolderNorm.lean,Mathlib/Topology/UnitInterval.lean 47 19 ['github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] nobody
8-1913
8 days ago
9-18749
9 days ago
0-10164
2 hours
33723 erdOne
author:erdOne
feat(Analytic): `℘'(z)² = 4 ℘(z)³ - g₂ ℘(z) - g₃` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-analysis 386/13 Mathlib/Algebra/Module/ZLattice/Basic.lean,Mathlib/Algebra/Order/Floor/Ring.lean,Mathlib/Analysis/Analytic/Order.lean,Mathlib/Analysis/Calculus/ContDiff/Basic.lean,Mathlib/Analysis/Calculus/ContDiff/Operations.lean,Mathlib/Analysis/Calculus/IteratedDeriv/Lemmas.lean,Mathlib/Analysis/Meromorphic/Basic.lean,Mathlib/Analysis/Meromorphic/Order.lean,Mathlib/Analysis/SpecialFunctions/Elliptic/Weierstrass.lean 9 32 ['erdOne', 'github-actions', 'loefflerd', 'vihdzp'] nobody
0-11717
3 hours ago
0-40115
11 hours ago
0-76056
21 hours
32740 LTolDe
author:LTolDe
feat: add IsNowhereDense helpers add new lemmas to prove `IsNowhereDense s` - IsNowhereDense.mono - Topology.IsInducing.isNowhereDense_image - IsNowhereDense.image_val these lemmas will help to prove the **Effros Theorem**, see [zulip thread](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Effros.20Theorem/with/558712441) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor large-import 24/1 Mathlib/Topology/GDelta/Basic.lean 1 7 ['ADedecker', 'LTolDe', 'dupuisf', 'github-actions'] dupuisf
assignee:dupuisf
0-81071
22 hours ago
27-76907
27 days ago
27-76938
27 days
33449 yuanyi-350
author:yuanyi-350
feat(ProbabilityTheory): Add Poisson limit theorem --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability large-import 102/5 Mathlib/Probability/Distributions/Poisson.lean,docs/1000.yaml 2 4 ['github-actions', 'vihdzp'] EtienneC30
assignee:EtienneC30
1-323
1 day ago
7-22137
7 days ago
7-22985
7 days

New contributors' PRs on the review queue

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
31610 rudynicolop
author:rudynicolop
feat(Computability/NFA): Kleene star closure for Regular Languages via NFA This PR constructs a Kleene star closure for non-epsilon NFAs, and proves that regular languages are closed under Kleene star. The NFA construction is `NFA.kstar`. The main theorems are: - `NFA.accepts_kstar`: demonstrates that `M.kstar` accepts the Kleene star closure of the language of `M`. - `IsRegular.kstar`: demonstrates that regular languages are closed under Kleene star. There is an onging zulip discussion about regular languages in Mathlib: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Regular.20languages.3A.20the.20review.20queue/with/553759136 This discussion is also tracked at #24205. Furthermore, the construction and proofs in this PR are heavily inspired by @TpmKranz from his #15651. #15651 supersedes this PR, so if it is accepted then this PR is not needed. --- - [x] depends on: #31038 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-computability 405/7 Mathlib/Computability/NFA.lean 1 5 ['ctchou', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot'] nobody
31-52122
1 month ago
37-55324
1 month ago
37-58274
37 days
32552 ksenono
author:ksenono
feat(SetTheory/Cardinal): helpers for Konig's theorem --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-set-theory 70/0 Mathlib/SetTheory/Cardinal/Arithmetic.lean,Mathlib/SetTheory/Cardinal/Basic.lean 2 33 ['SnirBroshi', 'b-mehta', 'github-actions', 'ksenono', 'staroperator', 'vihdzp'] b-mehta
assignee:b-mehta
25-28033
25 days ago
31-60876
1 month ago
31-60915
31 days
32600 PrParadoxy
author:PrParadoxy
feat(LinearAlgebra/Multilinear): composition of multilinear maps The composition of a multilinear map with a family of multilinear maps is a multilinear map indexed by a dependent sum. The result reduces to a lemma about the interaction of function application, `Sigma.curry`, and `Function.update`. This variant of `Function.apply_update` is included as `Sigma.apply_curry_update`. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor 40/0 Mathlib/Data/Sigma/Basic.lean,Mathlib/LinearAlgebra/Multilinear/Basic.lean 2 4 ['github-actions', 'goliath-klein', 'kbuzzard'] dwrensha
assignee:dwrensha
24-72904
24 days ago
29-67772
29 days ago
29-68033
29 days
32555 ksenono
author:ksenono
feat(Combinatorics/SimpleGraph/Matching): maximum and maximal matchings for Konig's theorem --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics new-contributor 127/1 Mathlib/Combinatorics/SimpleGraph/DegreeSum.lean,Mathlib/Combinatorics/SimpleGraph/Matching.lean 2 8 ['SnirBroshi', 'github-actions', 'ksenono'] awainverse
assignee:awainverse
21-32554
21 days ago
31-59598
1 month ago
31-59627
31 days
32570 ksenono
author:ksenono
feat(Combinatorics/SimpleGraph): bipartite subgraphs and vertex-disjoint graphs for Konig's theorem --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics new-contributor 22/0 Mathlib/Combinatorics/SimpleGraph/Bipartite.lean,Mathlib/Combinatorics/SimpleGraph/Subgraph.lean 2 10 ['SnirBroshi', 'github-actions'] kmill
assignee:kmill
21-32094
21 days ago
31-36397
1 month ago
31-36437
31 days
32355 bjornsolheim
author:bjornsolheim
feat(Geometry/Convex/Cone): define and characterize simplicial pointed cones Define finitely generated and simplicial pointed cones. Prove lemmas about simplicial (and generating simplicial) cones # Notes * I have tried alternative implementations (finite, finset, structure) If one can live with the extensional quantifier the finset seems better. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-convex-geometry 118/0 Mathlib.lean,Mathlib/Geometry/Convex/Cone/Simplicial.lean 2 1 ['github-actions'] nobody
20-48171
20 days ago
20-48663
20 days ago
30-53275
30 days
30872 rudynicolop
author:rudynicolop
feat(Computability/NFA): NFA closure under concatenation This PR proves that regular languages are closed under concatenation via a direct construction on `NFA`s without `εNFA` nor ε-transitions. The main new definitions and results include: - `M1.concat M2`, the concatenation of `NFA`s `M1` and `M2`, a direct construction without ε-transitions. - Theorem `accepts_concat : (M1.concat M2).accepts = M1.accepts * M2.accepts`, showing the correctness of the construction. - Theorem `IsRegular.mul`, showing that regular languages are closed under concatenation. --- - [x] depends on: #31038 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-computability maintainer-merge 104/7 Mathlib/Computability/NFA.lean 1 63 ['YaelDillies', 'ctchou', 'github-actions', 'lambda-fairy', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'rudynicolop'] YaelDillies
assignee:YaelDillies
19-51870
19 days ago
20-32325
20 days ago
38-44225
38 days
32826 felixpernegger
author:felixpernegger
feat(Data/Tuple/Sort): Permutation is monotone iff its the identity Sort of permutation is its inverse + Permutation is monotone iff its the identity new-contributor t-data 19/0 Mathlib/Data/Fin/Tuple/Sort.lean 1 1 ['github-actions'] TwoFX
assignee:TwoFX
19-43916
19 days ago
26-37030
26 days ago
26-37035
26 days
32910 felixpernegger
author:felixpernegger
feat(Data/Nat/Choose): two binomial coefficient sum identities This PR proves two well-known sum identities around binomial coefficients. While there are probably hundreds of such identities, these two seem to be well known enough to be in mathlib (i.e. are mentioned in the Wikipedia [article](https://en.wikipedia.org/wiki/Binomial_coefficient#math_8) about binomial coefficients). new-contributor t-data 31/0 Mathlib/Data/Nat/Choose/Sum.lean,Mathlib/Data/Nat/Choose/Vandermonde.lean 2 1 ['github-actions'] TwoFX
assignee:TwoFX
18-43886
18 days ago
23-79862
23 days ago
23-80188
23 days
33031 chiyunhsu
author:chiyunhsu
feat(Combinatorics/Enumerative/Partition): add combinatorial proof of Euler's partition theorem The new file EulerComb.lean contains the combinatorial proof of Euler's partition theorem. The analytic proof of the theorem and its generalization of Glaisher's Theorem has already been formalized in [Glaisher.lean](https://github.com/leanprover-community/mathlib4/blob/master/Mathlib/Combinatorics/Enumerative/Partition/Glaisher.lean). The generalization of the combinatorial proof from this file to Glaisher's Theorem is within reach. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-combinatorics new-contributor 531/0 Mathlib.lean,Mathlib/Combinatorics/Enumerative/Partition/EulerComb.lean 2 5 ['chiyunhsu', 'github-actions', 'tb65536', 'vihdzp'] b-mehta
assignee:b-mehta
16-43905
16 days ago
21-21430
21 days ago
21-21470
21 days
33109 felixpernegger
author:felixpernegger
feat(Data/Nat/Choose): Binomial inversion This PR adds binomial inversion (also called binomial transform), which is a useful method for proving binomial identities. It is tricky to find direct references to binomial inversion, but for example [this](https://en.wikipedia.org/wiki/Binomial_transform#Binomial_convolution) Wikipedia article mentions it ("The formula"). The first theorem ```alternating_sum_choose_mul_of_alternating_sum_choose_mul``` could be refined (we only need the hypothesis ```h``` up to some point), but this seems to needlessly complicate it. new-contributor 107/0 Mathlib.lean,Mathlib/Data/Nat/Choose/Inversion.lean 2 4 ['felixpernegger', 'github-actions', 'wwylele'] dagurtomas
assignee:dagurtomas
16-43895
16 days ago
19-57227
19 days ago
19-57208
19 days
33214 JJYYY-JJY
author:JJYYY-JJY
chore(Data/List/Rotate): add simp attributes * Refs #7987 (SC: Data/List/Rotate) * Add `@[simp]` to: `rotate_mod`, `rotate'_nil`, `rotate'_rotate'`, `rotate'_mod`, `rotate_rotate`, `getElem?_rotate`, `getElem_rotate`, `head?_rotate`, `map_rotate`. * Verification: `lake build Mathlib.Data.List.Rotate`. new-contributor t-data 7/0 Mathlib/Data/List/Rotate.lean 1 1 ['github-actions'] nobody
16-26228
16 days ago
16-37828
16 days ago
16-37868
16 days
31092 FlAmmmmING
author:FlAmmmmING
feat(Algebra/Group/ForwardDiff.lean): Add theorem `sum_shift_eq_fwdDiff_iter`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra new-contributor
label:t-algebra$
17/1 Mathlib/Algebra/Group/ForwardDiff.lean 1 18 ['BeibeiX0', 'FlAmmmmING', 'Ruben-VandeVelde', 'dagurtomas', 'github-actions', 'mathlib4-merge-conflict-bot'] dagurtomas
assignee:dagurtomas
14-19278
14 days ago
14-19302
14 days ago
40-15931
40 days
32745 LTolDe
author:LTolDe
feat(Topology/Algebra): add MulActionConst.lean add Topology/Algebra/MulActionConst.lean introduce class `ContinuousSMulConst` for a scalar multiplication that is continuous in the first argument, in analogy to `ContinuousConstSMul` define `MulAction.ball x U` as the set `U • {x}` given `[SMul G X] (x : X) (U : Set G)` The lemmas shown here will be useful to prove the **Effros Theorem**, see [zulip](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Effros.20Theorem/with/558712441). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-topology new-contributor 98/0 Mathlib.lean,Mathlib/Topology/Algebra/MulActionConst.lean 2 1 ['github-actions'] dagurtomas
assignee:dagurtomas
12-43912
12 days ago
27-73636
27 days ago
27-73686
27 days
33280 michelsol
author:michelsol
feat(MeasureTheory/Integral/IntervalIntegral): add variant `integral_deriv_eq_sub_uIoo` of 2nd theorem of calculus. Add a continuous on uIcc, differentiable on uIoo, deriv version of the 2nd fundamental theorem of calculus. This corresponds to what is written [here](https://en.wikipedia.org/wiki/Fundamental_theorem_of_calculus#Second_part). For example it makes it easier to compute the integral : ```lean4 ∫ x : ℝ in 0..1, (√(1 - x ^ 2))⁻¹ = ∫ x : ℝ in 0..1, deriv arcsin x = arcsin 1 - arcsin 0 ``` It is not possible to use [`interval_deriv_eq_sub`](https://leanprover-community.github.io/mathlib4_docs/Mathlib/MeasureTheory/Integral/IntervalIntegral/FundThmCalculus.html#intervalIntegral.integral_deriv_eq_sub) which requires differentiability on all of [0,1], as `arcsin` isn't differentiable at 1. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-measure-probability new-contributor 14/0 Mathlib/MeasureTheory/Integral/IntervalIntegral/FundThmCalculus.lean 1 1 ['github-actions'] EtienneC30
assignee:EtienneC30
10-43887
10 days ago
13-70512
13 days ago
13-70548
13 days
30391 rudynicolop
author:rudynicolop
feat(Data/List): list splitting definitions and lemmas This PR continues the work from #24395. Original PR: https://github.com/leanprover-community/mathlib4/pull/24395 new-contributor t-data 108/2 Mathlib/Data/List/Perm/Lattice.lean,Mathlib/Data/List/TakeDrop.lean 2 45 ['BoltonBailey', 'IlPreteRosso', 'TwoFX', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot', 'rudynicolop'] TwoFX
assignee:TwoFX
10-32805
10 days ago
19-50746
19 days ago
85-16073
85 days
30962 WangYiran01
author:WangYiran01
feat(Combinatorics/Enumerative): add lattice path lemmas and counts This PR adds definitions and theorems about monotone lattice paths: - Defines `pathCount`, `pathCountFrom`, `SubdiagProp`, and related structures. - Proves closed forms such as `pathCount_eq_closed`. - Adds Dyck/ballot subdiagonal property (`SubdiagProp`). All code builds successfully with `lake build`. t-combinatorics new-contributor 76/0 Mathlib.lean,Mathlib/Combinatorics/Enumerative/RecLatticePath.lean 2 3 ['github-actions', 'mathlib4-merge-conflict-bot'] awainverse
assignee:awainverse
10-9764
10 days ago
24-8899
24 days ago
44-8724
44 days
33299 kingiler
author:kingiler
feat: Add decidable membership for Interval Implemented membership and corresponding decidable instance for `Interval`. Related [#mathlib4 > Proposal: Add decidable membership for Interval](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Proposal.3A.20Add.20decidable.20membership.20for.20Interval/with/565438009). --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-order new-contributor 16/1 Mathlib/Order/Interval/Basic.lean 1 3 ['eric-wieser', 'github-actions', 'kingiler'] Vierkantor
assignee:Vierkantor
9-43903
9 days ago
13-27987
13 days ago
13-32569
13 days
32744 NoneMore
author:NoneMore
feat(ModelTheory/Definablity): add `DefinableFun` definition and lemmas This PR adds two basic shapes of definable sets and `DefinableFun` definition with relevant lemmas. The main result is `Set.Definable.preimage_of_map` asserting that the preimage of a definable set under a definable map is definable. There are also some tool lemmas derived by the preimage lemma. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic new-contributor 151/0 Mathlib/ModelTheory/Definability.lean 1 58 ['NoneMore', 'github-actions', 'staroperator'] fpvandoorn
assignee:fpvandoorn
6-75211
6 days ago
27-28561
27 days ago
27-73864
27 days
33481 NoneMore
author:NoneMore
feat(ModelTheory/Encoding): add `Countable` instances for (bounded) formulas in countable languages Prepare for the OTT proof. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic new-contributor 27/0 Mathlib/ModelTheory/Encoding.lean 1 1 ['github-actions'] nobody
5-27659
5 days ago
6-10077
6 days ago
6-10112
6 days
33520 NoneMore
author:NoneMore
feat(ModelTheory/ElementarySubstructures): add a variant of Tarski-Vaught test taking sets as input There should exist an `ElementarySubstructure.copy` such that we can directly bundle the set itself instaed of its closure as an elementary substructure. The other direction depends on #33458. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic new-contributor 63/0 Mathlib/ModelTheory/ElementarySubstructures.lean 1 1 ['github-actions'] nobody
4-81098
4 days ago
5-6995
5 days ago
5-7028
5 days
33221 stepan2698-cpu
author:stepan2698-cpu
feat: definition of an intertwining map Adds the definition of an intertwining map of representations, with an instance of an A-module structure. Proves that a multiplication by a central element is an intertwining map. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra new-contributor
label:t-algebra$
355/11 Mathlib.lean,Mathlib/RepresentationTheory/Intertwining.lean,Mathlib/RepresentationTheory/Irreducible.lean,Mathlib/RepresentationTheory/Subrepresentation.lean 4 1 ['github-actions'] ocfnash
assignee:ocfnash
4-43887
4 days ago
16-31297
16 days ago
16-31337
16 days
33443 sahanwijetunga
author:sahanwijetunga
feat: Define Isometries of Bilinear Spaces --- We define Isometries of Bilinear Spaces, closely following the implementation of isometries of quadratic spaces. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra new-contributor
label:t-algebra$
275/0 Mathlib.lean,Mathlib/LinearAlgebra/BilinearForm/Isometry.lean,Mathlib/LinearAlgebra/BilinearForm/IsometryEquiv.lean 3 1 ['github-actions'] dagurtomas
assignee:dagurtomas
4-43881
4 days ago
7-52544
7 days ago
7-52582
7 days
33118 thomaskwaring
author:thomaskwaring
feat(Combinatorics/SimpleGraph/Acyclic): every graph has a spanning forest. We show that every graph has a spanning forest: defined to be an acyclic subgraph with the same reachability relation as the larger graph. As a special case, every connected graph has a spanning tree. --- Each of these results (spanning forest & spanning tree) are proved in two versions: a general case where the forest / tree is found by extending a given acyclic subgraph, and the special case where that subgraph is empty. - [ ] depends on: #32043 t-combinatorics new-contributor 29/5 Mathlib/Combinatorics/SimpleGraph/Acyclic.lean 1 6 ['SnirBroshi', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'thomaskwaring', 'vlad902'] nobody
4-41436
4 days ago
5-31087
5 days ago
5-34275
5 days
33599 nielstron
author:nielstron
feat(Computability/ContextFreeGrammar): closure under union --- This PR picks up https://github.com/leanprover-community/mathlib4/pull/13514 and resolves the outstanding errors. - [ ] depends on #33592 [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-computability 506/0 Mathlib/Computability/ContextFreeGrammar.lean 1 1 ['github-actions'] nobody
2-77777
2 days ago
3-1838
3 days ago
3-1879
3 days
33458 NoneMore
author:NoneMore
feat(ModelTheory): add lifting for embeddings to languages with constants Prepare for a generalized Tarski-Vaught test with a set as input instead of a substructure. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-logic new-contributor 46/0 Mathlib/ModelTheory/ElementaryMaps.lean,Mathlib/ModelTheory/LanguageMap.lean 2 1 ['github-actions'] fpvandoorn
assignee:fpvandoorn
2-43898
2 days ago
6-74831
6 days ago
6-74868
6 days
33478 anishrajeev
author:anishrajeev
feat(ModelTheory): define a subset of the topology over complete types Define a subset of the Stone Space over a language expanded with countably many constants. Define the proposition to indicate if a language is countable. The subset's density and openness is a future goal to prove (have a branch where it is almost finished), in pursuit of formalizing the proof of the Omitting Types Theorem via properties of Baire spaces. [ ] depends on: #32215 [ ] depends on: #32546 new-contributor 160/1 Mathlib.lean,Mathlib/ModelTheory/Topology/Types.lean,Mathlib/ModelTheory/Types.lean,Mathlib/Tactic/Linter/DirectoryDependency.lean 4 5 ['NoneMore', 'anishrajeev', 'github-actions'] RemyDegenne
assignee:RemyDegenne
2-43895
2 days ago
6-38706
6 days ago
6-38686
6 days
33662 Pjotr5
author:Pjotr5
feat(Algebra/Order/BigOperators/Expect): add lemmas and strict variants ### Summary - Combine `le_expect_nonempty_of_subadditive` and `le_expect_of_subadditive` into a single lemma `le_expect_of_subadditive`. The extra assumptions `(hs : s.Nonempty)` and `(h_zero : m 0 = 0)` are unnecessary (since `m 0 = 0` follows from `h_div`). This requires a small downstream update to `Mathlib/Analysis/RCLike/Basic.lean` (`norm_expect_le`). - Add strict-inequality variants: `expect_lt_expect`, `expect_lt`, `lt_expect`. - Add existence lemmas: `exists_le_of_expect_le_expect`, `exists_le_of_le_expect`, `exists_le_of_expect_le`, and `exists_lt_of_expect_lt_expect`. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor 46/16 Mathlib/Algebra/Order/BigOperators/Expect.lean,Mathlib/Analysis/RCLike/Basic.lean 2 1 ['github-actions'] nobody
2-11639
2 days ago
2-14216
2 days ago
2-14198
2 days
33431 gululu996-ui
author:gululu996-ui
feat(Combinatorics/SimpleGraph/Bipartite): characterize bipartite simplegraphs by even cycles Add the classical characterization of bipartite simple graphs: a simple graph is bipartite if and only if every cycle has even length. Previously, mathlib has the definition of `IsBipartite` for `SimpleGraph` and various lemmas about bipartite graphs, but it does not provide this equivalence in a single theorem, so users have to reprove or reassemble it from existing results. Prove the forward direction by showing a 2-coloring alternates along any walk, so every cycle must have even length. Prove the converse by showing that if an odd cycle exists then no bipartition is possible, hence if all cycles are even the graph admits a bipartition. t-combinatorics new-contributor 185/1 Mathlib/Combinatorics/SimpleGraph/Bipartite.lean 1 3 ['NickAdfor', 'github-actions'] nobody
1-83590
1 day ago
4-465
4 days ago
8-2145
8 days
33592 nielstron
author:nielstron
feat(Computability/ContextFreeGrammar): mapping between two types of nonterminal symbols --- This PR picks up https://github.com/leanprover-community/mathlib4/pull/15895 and resolves the failing lemma by redefining Good symbols. I checked that https://github.com/leanprover-community/mathlib4/pull/13514 builds correctly when based on this build. PR for that is #33599 This is my first contribution please let me know of any changes I should outline. [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-computability 162/0 Mathlib/Computability/ContextFreeGrammar.lean 1 1 ['github-actions', 'madvorak'] nobody
1-79411
1 day ago
3-2385
3 days ago
3-2910
3 days
33216 stepan2698-cpu
author:stepan2698-cpu
feat: Schur's lemma over an algebraically closed field Adds a new file with facts about algebra representations. Proves Schur's lemma (any endomorphism of an algebra representation over an algebraically closed field is scalar) and proves that every finite-dimensional representation of a commutative algebra over an algebraically closed field is one-dimensional. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-algebra new-contributor
label:t-algebra$
80/0 Mathlib.lean,Mathlib/RepresentationTheory/AlgebraRepresentation/Basic.lean 2 6 ['copilot-pull-request-reviewer', 'github-actions'] riccardobrasca
assignee:riccardobrasca
1-56606
1 day ago
16-34389
16 days ago
16-34426
16 days
32856 stepan2698-cpu
author:stepan2698-cpu
feat: definition of an irreducible representation Define irreducible monoid representations over a field and prove that a monoid representation is irreducible iff the corresponding module over the monoid algebra is simple. t-algebra new-contributor
label:t-algebra$
129/10 Mathlib.lean,Mathlib/RepresentationTheory/Irreducible.lean,Mathlib/RepresentationTheory/Subrepresentation.lean 3 21 ['Whysoserioushah', 'erdOne', 'github-actions', 'stepan2698-cpu'] kim-em
assignee:kim-em
1-56577
1 day ago
25-55329
25 days ago
25-55363
25 days
33668 Citronhat
author:Citronhat
feat(PMF): add lintegral formulas for PMF This PR introduces two lemmas describing the `lintegral` of a function with respect to the measure induced by a probability mass function: - `PMF.lintegral_eq_tsum` - `PMF.lintegral_eq_sum` These are the `ℝ≥0∞` analogues of the existing Bochner `integral` formulas `integral_eq_tsum` and `integral_eq_sum`. They could be useful for reasoning about expectations and integrability. In addition, the proof of `integral_eq_sum` is simplified by deriving it directly from `integral_eq_tsum` using `tsum_fintype`. t-measure-probability new-contributor 14/5 Mathlib/Probability/ProbabilityMassFunction/Integrals.lean 1 1 ['github-actions'] nobody
1-49044
1 day ago
1-82471
1 day ago
1-82512
1 day
33709 wangying11123
author:wangying11123
feat(Analysis/Convex/Between):Add wbtw_of_sameRay_vsub_left add wbtw_of_sameRay_vsub_left Main additions `wbtw_of_sameRay_vsub_left` if the vectors from a point x to points y and z lie on the same ray, then y is weakly between x and z, or z is weakly between x and y. new-contributor 24/0 Mathlib/Analysis/Convex/Between.lean 1 2 ['github-actions'] nobody
1-7430
1 day ago
1-8218
1 day ago
1-8201
1 day
33411 IlPreteRosso
author:IlPreteRosso
feat(Analysis/DiscreteConvolution): Discrete convolution API basics This is the first PR is a series of PRs towards the proposed API and ℓ1 Banach algebra. Defines discrete convolution of functions `f : M → E` and `g : M → E'` over a monoid `M` using a bilinear map `L : E →ₗ[S] E' →ₗ[S] F`: `(f ⋆[L] g) x = ∑' (a, b) : mulFiber x, L (f a) (g b)` where `abbrev mulFiber (x : M) : Set (M × M) := Set.mulAntidiagonal Set.univ Set.univ x` Declaration: AI tools used for debugging/facilitating peripheral commands (e.g. bash commands), docstrings, refactoring and condensing existing formalization. I welcome reviews on humanizing doctrings. Personally speaking, AI does a better job at writing those than what I can do. My brain isn't in the right condition to write human language after coding and debugging for hours and hours. The philosophy of me using AI tools is "hey gather information/spot patterns for me", other than "give me the answer". t-analysis new-contributor 489/0 Mathlib.lean,Mathlib/Analysis/DiscreteConvolution/Basic.lean 2 11 ['IlPreteRosso', 'github-actions', 'j-loreaux'] urkud
assignee:urkud
0-83126
23 hours ago
1-26124
1 day ago
8-20494
8 days
33688 Citronhat
author:Citronhat
feat(PMF): add expectation lemmas for Poisson PMF This PR adds some basic results about the Poisson distribution, its `PMF`, and its expectation. **New lemmas:** * `poissonPMF_apply` — an unfolding lemma for `poissonPMF`. * `poissonPMFReal_mul_eq_succ_mul` — the standard recursion identity for the Poisson mass function. * `poissonPMFReal_hasSum_nmul` — shows that `fun n ↦ poissonPMFReal r n * n` has sum `r`. * `poissonPMF_tsum_nmul` — the corresponding identity at the level of the `PMF`. * `poissonPMF_coe_tsum_nmul` — the same result after coercion to `ℝ`. Both `ℝ`-valued and `ℝ≥0∞`-valued formulations are included so that these results can be used conveniently in both Lebesgue and Bochner integration contexts. t-measure-probability new-contributor 21/0 Mathlib/Probability/Distributions/Poisson.lean 1 2 ['Citronhat', 'github-actions'] nobody
0-53152
14 hours ago
1-52943
1 day ago
1-52977
1 day
28546 Sfgangloff
author:Sfgangloff
feat(SymbolicDynamics): basic setup of Zd, full shift, cylinders, pat… This PR adds a **group-generic** foundation for symbolic dynamics over an arbitrary group `G`, together with convenient specializations for `ℤ` and `ℤ^d`. Summary of additions: - **Full shift and shift action** - `abbrev FullShift (A G) := G → A` (inherits product topology from the Π-type). - Right shift `shift g x` with convention `(shift g x) h = x (h * g)`. - **Cylinders and topology** - `cylinder U x : Set (G → A)` for finite `U : Finset G`. - Cylinders are open under `[DiscreteTopology A]`; with a finite alphabet they are also closed. - Equality with dependent products: `cylinder U x = Set.pi (↑U) (fun i => ({x i} : Set A))`, enabling use of the `Set.pi` API. - **Patterns, occurrences, and subshifts** - `Pattern A G` with finite `support : Finset G` and `data : support → A`. - `Pattern.occursIn p x g` (occurrence at translate `g`) and the expected shift law. - `forbids F` and `Subshift A G` (closed, shift-invariant subsets). - `FixedSupport A G U` with an equivalence to `(U → A)` to obtain finiteness. - **Language on finite shapes and counting** - `languageOn X U`, `languageCardOn X U`, and `patternCountOn Y U`. - **Entropy along a shape sequence** - `limsupAtTop` (as an `sInf` of eventual upper bounds). - `entropyAlong X F hF := limsup (log (patternCountOn X (F n) + 1) / |F n|)` for any nonempty finite shapes `F : ℕ → Finset G` (the `+ 1` avoids `log 0`). - **Specializations** - `IntShapes`: segments `[-n,n]` on `Multiplicative ℤ`, with `entropy_Z`. - `ZdShapes`: boxes `[-n,n]^d` on `ℤ^d` (as functions `Fin d → ℤ`), with `entropy_Zd`. Mathematical remarks: - The API is **shape-parametric**: entropy is defined along user-provided finite shapes. - On **amenable** groups, using a **Følner** sequence yields a canonical value (Ornstein–Weiss). This PR does not assume amenability; the family of shapes is an explicit input. Motivation: Provide a clean, reusable base for symbolic dynamics on groups in mathlib. Future work: - Add a Følner predicate and prove shape-independence / limit existence on amenable groups. - Expand the `ℤ`/`ℤ^d` toolkit (alternative shapes, mixing, factors). - Develop 1D theory and, longer-term, multidimensional SFT results (e.g. along the lines of Hochman–Meyerovitch). t-dynamics new-contributor 756/0 Mathlib.lean,Mathlib/Dynamics/SymbolicDynamics/Basic.lean,Mathlib/Tactic/Translate/ToAdditive.lean 3 156 ['Sfgangloff', 'eric-wieser', 'github-actions', 'kckennylau', 'mathlib4-merge-conflict-bot', 'sgouezel'] sgouezel
assignee:sgouezel
0-52560
14 hours ago
1-24014
1 day ago
87-32910
87 days
28708 sjh227
author:sjh227
feat(LinearAlgebra): define row- and column-stochastic matrices This PR defines row- and column-stochastic matrices, and relates them to doubly stochastic matrices (which are already in mathlib). --- new-contributor t-data 255/6 Mathlib.lean,Mathlib/Algebra/Group/Submonoid/Defs.lean,Mathlib/Analysis/Convex/DoublyStochasticMatrix.lean,Mathlib/LinearAlgebra/Matrix/Stochastic.lean 4 29 ['dupuisf', 'github-actions', 'j-loreaux', 'mathlib4-merge-conflict-bot', 'sjh227'] pechersky
assignee:pechersky
0-43909
12 hours ago
3-56160
3 days ago
4-47755
4 days
33493 michelsol
author:michelsol
feat(RingTheory/Polynomial): An explicit formula for the Chebyshev polynomials of the first kind Adds the following explicit formula on the Chebyshev polynomial of the first kind of order n. ${ T_{n}(x)\ =\ \sum \limits _{k=0}^{\lfloor {\frac {n}{2}}\rfloor } {\binom {n}{2k}} \left(\ X^{2}-1\ \right)^{k}\ X^{n-2k}}$ This explicit formula can be found [here](https://en.wikipedia.org/wiki/Chebyshev_polynomials#Explicit_expressions). There is a proof using complex numbers but it only works if the ring R = ℂ. The proof here is by induction and works in a commutative ring R. Mathlib seems to extend the definition of Chebyshev polynomials for $n \in \mathbb{Z}$ but this would make the formula more cumbersome with `n.natAbs` in place of `n`'s, so I expressed it on `n : ℕ` directly. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-ring-theory 51/1 Mathlib/RingTheory/Polynomial/Chebyshev.lean 1 7 ['YuvalFilmus', 'erdOne', 'github-actions', 'metakunt', 'michelsol'] nobody
3-65854
3 days ago
3-65855
3 days ago
4-58721
4 days
33539 BryceT233
author:BryceT233
feat(RingTheory/MvPolynomial): powers of ideal of variables proved some helper results for powers of the ideal of variables in `MvPolynomial` --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-ring-theory 98/1 Mathlib/RingTheory/MvPolynomial/Ideal.lean 1 8 ['BryceT233', 'erdOne', 'github-actions', 'vihdzp'] erdOne
assignee:erdOne
0-43898
12 hours ago
4-19311
4 days ago
4-19343
4 days
33355 0xTerencePrime
author:0xTerencePrime
feat(Combinatorics/SimpleGraph/Connectivity): define vertex connectivity 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`: vertices remain reachable after removing strictly fewer than `k` other vertices. - `SimpleGraph.IsVertexConnected`: a graph is `k`-vertex-connected if its order is strictly greater than `k` and any two distinct vertices are `k`-vertex-reachable. Includes basic characterizations for $k=0$ and $k=1$, along with monotonicity lemmas (`anti` and `mono`). t-combinatorics new-contributor 160/0 Mathlib.lean,Mathlib/Combinatorics/SimpleGraph/Connectivity/VertexConnectivity.lean,Mathlib/Combinatorics/SimpleGraph/IsolateVerts.lean 3 87 ['0xTerencePrime', 'SnirBroshi', 'github-actions', 'vihdzp'] nobody
0-72011
20 hours ago
11-3330
11 days ago
11-3362
11 days
29960 yonggyuchoimath
author:yonggyuchoimath
feat(Algebra/Category/Ring): equalizers of pushout maps of tensor product inclusions This PR defines a ring map `S →ₗ[R] S ⊗[R] S : s ↦ (s ⊗ₜ[R] 1) - (1 ⊗ₜ[R] s)` for an `R`-algebra `S`, and show that its kernel is exactly (the image of) `R` if `S` is faithfully flat over `R`. Changes: * `TensorProduct.AlgebraTensorModule.distribBaseChange`: Origianlly takes `M` and `N`, where `M` is an `R`-module with an additional instance `IsScalarTower R A M`. This is unnecessary, so I changed the `M` and `N` into `N` and `Q`, now both of which are merely modules over `R`. Main results : * Add compatibility of `Algebra.TensorProduct.includeLeft` (or `Algebra.TensorProduct.includeRight`) with `TensorProduct.AlgebraTensorModule.distribBaseChange` and `LinearMap.lTensor` * Define `Algebra.TensorProduct.includeLeftSubRight`, which is the `R`-linear map `S →ₗ[R] S ⊗[R] S` sending `s : S` to `(s ⊗ₜ[R] 1) - (1 ⊗ₜ[R] s)`. * `Algebra.isEffective_of_faithfullyFlat`: the pair `algebraMap : R → S` and `includeLeftSubRight R S : S → S ⊗[R] S` is exact if `S` is a faithfully flat `R`-algebra. --- - [x] depends on: #30806 new-contributor t-ring-theory 214/1 Mathlib.lean,Mathlib/LinearAlgebra/TensorProduct/Tower.lean,Mathlib/RingTheory/TensorProduct/IncludeLeftSubRight.lean,Mathlib/RingTheory/TensorProduct/Maps.lean 4 20 ['erdOne', 'github-actions', 'mathlib4-dependent-issues-bot', 'mathlib4-merge-conflict-bot', 'yonggyuchoimath'] PatrickMassot and erdOne
assignee:PatrickMassot assignee:erdOne
0-36773
10 hours ago
0-36773
10 hours ago
54-69317
54 days
33714 idontgetoutmuch
author:idontgetoutmuch
Riemannian metrics exist II Supersedes https://github.com/leanprover-community/mathlib4/pull/33519 --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) t-differential-geometry new-contributor 1269/0 Mathlib.lean,Mathlib/Geometry/Manifold/ExistsRiemannianMetricTangentSpace.lean,Mathlib/Geometry/Manifold/PartitionOfUnity.lean 3 1 ['github-actions'] nobody
0-11802
3 hours ago
0-11802
3 hours ago
0-84085
23 hours
33744 bilichboris
author:bilichboris
feat(RingTheory): Class Group of a Unique Factorization Domain is trivial Add a theorem that the class group of a unique factorization domain is trivial. Together with the PR relating `ClassGroup` to `PicardGroup`, this will close a TODO in `Mathlib.RingTheory.PicardGroup` that the Picard Group of a UFD is trivial. --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor t-ring-theory 712/0 Mathlib.lean,Mathlib/RingTheory/UniqueFactorizationDomain/ClassGroup.lean 2 3 ['github-actions', 'jcommelin'] nobody
0-9484
2 hours ago
0-14702
4 hours ago
0-14743
4 hours
32740 LTolDe
author:LTolDe
feat: add IsNowhereDense helpers add new lemmas to prove `IsNowhereDense s` - IsNowhereDense.mono - Topology.IsInducing.isNowhereDense_image - IsNowhereDense.image_val these lemmas will help to prove the **Effros Theorem**, see [zulip thread](https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/Effros.20Theorem/with/558712441) --- [![Open in Gitpod](https://gitpod.io/button/open-in-gitpod.svg)](https://gitpod.io/from-referrer/) new-contributor large-import 24/1 Mathlib/Topology/GDelta/Basic.lean 1 7 ['ADedecker', 'LTolDe', 'dupuisf', 'github-actions'] dupuisf
assignee:dupuisf
0-81071
22 hours ago
27-76907
27 days ago
27-76938
27 days

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