Short complexes #
This file defines the category ShortComplex C
of diagrams
X₁ ⟶ X₂ ⟶ X₃
such that the composition is zero.
Note: This structure ShortComplex C
was first introduced in
the Liquid Tensor Experiment.
A short complex in a category C
with zero morphisms is the datum
of two composable morphisms f : X₁ ⟶ X₂
and g : X₂ ⟶ X₃
such that
f ≫ g = 0
.
- X₁ : C
the first (left) object of a
ShortComplex
- X₂ : C
the second (middle) object of a
ShortComplex
- X₃ : C
the third (right) object of a
ShortComplex
- f : self.X₁ ⟶ self.X₂
the first morphism of a
ShortComplex
- g : self.X₂ ⟶ self.X₃
the second morphism of a
ShortComplex
- zero : CategoryTheory.CategoryStruct.comp self.f self.g = 0
the composition of the two given morphisms is zero
Instances For
the composition of the two given morphisms is zero
Morphisms of short complexes are the commutative diagrams of the obvious shape.
- τ₁ : S₁.X₁ ⟶ S₂.X₁
the morphism on the left objects
- τ₂ : S₁.X₂ ⟶ S₂.X₂
the morphism on the middle objects
- τ₃ : S₁.X₃ ⟶ S₂.X₃
the morphism on the right objects
- comm₁₂ : CategoryTheory.CategoryStruct.comp self.τ₁ S₂.f = CategoryTheory.CategoryStruct.comp S₁.f self.τ₂
the left commutative square of a morphism in
ShortComplex
- comm₂₃ : CategoryTheory.CategoryStruct.comp self.τ₂ S₂.g = CategoryTheory.CategoryStruct.comp S₁.g self.τ₃
the right commutative square of a morphism in
ShortComplex
Instances For
the left commutative square of a morphism in ShortComplex
the right commutative square of a morphism in ShortComplex
The identity morphism of a short complex.
Equations
- One or more equations did not get rendered due to their size.
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The composition of morphisms of short complexes.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Equations
- CategoryTheory.ShortComplex.instCategory = CategoryTheory.Category.mk ⋯ ⋯ ⋯
A constructor for morphisms in ShortComplex C
when the commutativity conditions
are not obvious.
Equations
- CategoryTheory.ShortComplex.homMk τ₁ τ₂ τ₃ comm₁₂ comm₂₃ = { τ₁ := τ₁, τ₂ := τ₂, τ₃ := τ₃, comm₁₂ := comm₁₂, comm₂₃ := comm₂₃ }
Instances For
Equations
- CategoryTheory.ShortComplex.instZeroHom = { zero := { τ₁ := 0, τ₂ := 0, τ₃ := 0, comm₁₂ := ⋯, comm₂₃ := ⋯ } }
Equations
- CategoryTheory.ShortComplex.instHasZeroMorphisms = CategoryTheory.Limits.HasZeroMorphisms.mk ⋯ ⋯
The first projection functor ShortComplex C ⥤ C
.
Equations
- CategoryTheory.ShortComplex.π₁ = { obj := fun (S : CategoryTheory.ShortComplex C) => S.X₁, map := fun {X Y : CategoryTheory.ShortComplex C} (f : X ⟶ Y) => f.τ₁, map_id := ⋯, map_comp := ⋯ }
Instances For
The second projection functor ShortComplex C ⥤ C
.
Equations
- CategoryTheory.ShortComplex.π₂ = { obj := fun (S : CategoryTheory.ShortComplex C) => S.X₂, map := fun {X Y : CategoryTheory.ShortComplex C} (f : X ⟶ Y) => f.τ₂, map_id := ⋯, map_comp := ⋯ }
Instances For
The third projection functor ShortComplex C ⥤ C
.
Equations
- CategoryTheory.ShortComplex.π₃ = { obj := fun (S : CategoryTheory.ShortComplex C) => S.X₃, map := fun {X Y : CategoryTheory.ShortComplex C} (f : X ⟶ Y) => f.τ₃, map_id := ⋯, map_comp := ⋯ }
Instances For
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
Equations
- ⋯ = ⋯
The natural transformation π₁ ⟶ π₂
induced by S.f
for all S : ShortComplex C
.
Equations
- CategoryTheory.ShortComplex.π₁Toπ₂ = { app := fun (S : CategoryTheory.ShortComplex C) => S.f, naturality := ⋯ }
Instances For
The natural transformation π₂ ⟶ π₃
induced by S.g
for all S : ShortComplex C
.
Equations
- CategoryTheory.ShortComplex.π₂Toπ₃ = { app := fun (S : CategoryTheory.ShortComplex C) => S.g, naturality := ⋯ }
Instances For
The short complex in D
obtained by applying a functor F : C ⥤ D
to a
short complex in C
, assuming that F
preserves zero morphisms.
Equations
- S.map F = CategoryTheory.ShortComplex.mk (F.map S.f) (F.map S.g) ⋯
Instances For
The morphism of short complexes S.map F ⟶ S.map G
induced by
a natural transformation F ⟶ G
.
Equations
- S.mapNatTrans τ = { τ₁ := τ.app S.X₁, τ₂ := τ.app S.X₂, τ₃ := τ.app S.X₃, comm₁₂ := ⋯, comm₂₃ := ⋯ }
Instances For
The isomorphism of short complexes S.map F ≅ S.map G
induced by
a natural isomorphism F ≅ G
.
Equations
- S.mapNatIso τ = { hom := S.mapNatTrans τ.hom, inv := S.mapNatTrans τ.inv, hom_inv_id := ⋯, inv_hom_id := ⋯ }
Instances For
The functor ShortComplex C ⥤ ShortComplex D
induced by a functor C ⥤ D
which
preserves zero morphisms.
Equations
- One or more equations did not get rendered due to their size.
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A constructor for isomorphisms in the category ShortComplex C
Equations
- One or more equations did not get rendered due to their size.
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The opposite ShortComplex
in Cᵒᵖ
associated to a short complex in C
.
Equations
- S.op = CategoryTheory.ShortComplex.mk S.g.op S.f.op ⋯
Instances For
The opposite morphism in ShortComplex Cᵒᵖ
associated to a morphism in ShortComplex C
Equations
- CategoryTheory.ShortComplex.opMap φ = { τ₁ := φ.τ₃.op, τ₂ := φ.τ₂.op, τ₃ := φ.τ₁.op, comm₁₂ := ⋯, comm₂₃ := ⋯ }
Instances For
The ShortComplex
in C
associated to a short complex in Cᵒᵖ
.
Equations
- S.unop = CategoryTheory.ShortComplex.mk S.g.unop S.f.unop ⋯
Instances For
The morphism in ShortComplex C
associated to a morphism in ShortComplex Cᵒᵖ
Equations
- CategoryTheory.ShortComplex.unopMap φ = { τ₁ := φ.τ₃.unop, τ₂ := φ.τ₂.unop, τ₃ := φ.τ₁.unop, comm₁₂ := ⋯, comm₂₃ := ⋯ }
Instances For
The obvious functor (ShortComplex C)ᵒᵖ ⥤ ShortComplex Cᵒᵖ
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The obvious functor ShortComplex Cᵒᵖ ⥤ (ShortComplex C)ᵒᵖ
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The obvious equivalence of categories (ShortComplex C)ᵒᵖ ≌ ShortComplex Cᵒᵖ
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The canonical isomorphism S.unop.op ≅ S
for a short complex S
in Cᵒᵖ
Equations
- S.unopOp = (CategoryTheory.ShortComplex.opEquiv C).counitIso.app S
Instances For
The canonical isomorphism S.op.unop ≅ S
for a short complex S
Equations
- S.opUnop = ((CategoryTheory.ShortComplex.opEquiv C).unitIso.app (Opposite.op S)).unop