Complementary embeddings #
Given two embeddings e₁ : c₁.Embedding c and e₂ : c₂.Embedding c
of complex shapes, we introduce a property e₁.AreComplementary e₂
saying that the image subsets of the indices of c₁ and c₂ form
a partition of the indices of c.
If e₁.IsTruncLE and e₂.IsTruncGE, and K : HomologicalComplex C c,
we construct a quasi-isomorphism shortComplexTruncLEX₃ToTruncGE between
the cokernel of K.ιTruncLE e₁ : K.truncLE e₁ ⟶ K and K.truncGE e₂.
Two embedding e₁ and e₂ into a complex shape c : ComplexShape ι
are complementary when the range of e₁.f and e₂.f form a partition of ι.
Instances For
Given complementary embeddings of complex shapes
e₁ : Embedding c₁ c and e₂ : Embedding c₂ c, this is
the obvious map ι₁ ⊕ ι₂ → ι from the sum of the index
types of c₁ and c₂ to the index type of c.
Equations
- ComplexShape.Embedding.AreComplementary.fromSum e₁ e₂ (Sum.inl i₁) = e₁.f i₁
- ComplexShape.Embedding.AreComplementary.fromSum e₁ e₂ (Sum.inr i₂) = e₂.f i₂
Instances For
Given complementary embeddings of complex shapes
e₁ : Embedding c₁ c and e₂ : Embedding c₂ c, this is
the obvious bijection ι₁ ⊕ ι₂ ≃ ι from the sum of the index
types of c₁ and c₂ to the index type of c.
Equations
Instances For
Auxiliary definition for desc.
Equations
- ComplexShape.Embedding.AreComplementary.desc.aux X i j hij = hij ▸ Equiv.refl (X i)
Instances For
Auxiliary definition for desc.
Instances For
If ι₁ and ι₂ are the index types of complementary embeddings into a
complex shape of index type ι, this is a constructor for (dependent) maps from ι,
which takes as inputs the "restrictions" to ι₁ and ι₂.
Equations
Instances For
Variant of hom_ext.
If e₁ and e₂ are complementary embeddings into a complex shape c,
indices i₁ and i₂ are at the boundary if c.Rel (e₁.f i₁) (e₂.f i₂).
Instances For
If ac : AreComplementary e₁ e₂ (with e₁ : ComplexShape.Embedding c₁ c and
e₂ : ComplexShape.Embedding c₂ c), and i₁ belongs to e₁.BoundaryLE,
then this is the (unique) index i₂ of c₂ such that ac.Boundary i₁ i₂.
Instances For
If ac : AreComplementary e₁ e₂ (with e₁ : ComplexShape.Embedding c₁ c and
e₂ : ComplexShape.Embedding c₂ c), and i₂ belongs to e₂.BoundaryGE,
then this is the (unique) index i₁ of c₁ such that ac.Boundary i₁ i₂.
Instances For
The bijection Subtype e₁.BoundaryLE ≃ Subtype e₂.BoundaryGE when
e₁ and e₂ are complementary embeddings of complex shapes.
Equations
- One or more equations did not get rendered due to their size.
Instances For
When e₁ and e₂ are complementary embeddings of complex shapes, with
e₁.IsTruncLE and e₂.IsTruncGE, then this is the canonical quasi-isomorphism
(K.shortComplexTruncLE e₁).X₃ ⟶ K.truncGE e₂ where
(K.shortComplexTruncLE e₁).X₃ is the cokernel of K.ιTruncLE e₁ : K.truncLE e₁ ⟶ K.
Equations
- K.shortComplexTruncLEX₃ToTruncGE ac = CategoryTheory.Limits.cokernel.desc (K.ιTruncLE e₁) (K.πTruncGE e₂) ⋯