The mapping cone of a morphism of cochain complexes #
In this file, we study the homotopy cofiber HomologicalComplex.homotopyCofiber
of a morphism φ : F ⟶ G
of cochain complexes indexed by ℤ
. In this case,
we redefine it as CochainComplex.mappingCone φ
. The API involves definitions
mappingCone.inl φ : Cochain F (mappingCone φ) (-1)
,mappingCone.inr φ : G ⟶ mappingCone φ
,mappingCone.fst φ : Cocycle (mappingCone φ) F 1
andmappingCone.snd φ : Cochain (mappingCone φ) G 0
.
Equations
The mapping cone of a morphism of cochain complexes indexed by ℤ
.
Instances For
The left inclusion in the mapping cone, as a cochain of degree -1
.
Equations
- CochainComplex.mappingCone.inl φ = CochainComplex.HomComplex.Cochain.mk fun (p q : ℤ) (hpq : p + -1 = q) => HomologicalComplex.homotopyCofiber.inlX φ p q (_ : (ComplexShape.up ℤ).Rel q p)
Instances For
The right inclusion in the mapping cone.
Instances For
The first projection from the mapping cone, as a cocyle of degree 1
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The second projection from the mapping cone, as a cochain of degree 0
.
Equations
Instances For
In order to obtain identities of cochains involving inl
, inr
, fst
and snd
,
it is often convenient to use an ext
lemma, and use simp lemmas like inl_v_f_fst_v
,
but it is sometimes possible to get identities of cochains by using rewrites of
identities of cochains like inl_fst
. Then, similarly as in category theory,
if we associate the compositions of cochains to the right as much as possible,
it is also interesting to have reassoc
variants of lemmas, like inl_fst_assoc
.
Given φ : F ⟶ G
, this is the cochain in Cochain (mappingCone φ) K n
that is
constructed from two cochains α : Cochain F K m
(with m + 1 = n
) and β : Cochain F K n
.
Equations
- CochainComplex.mappingCone.descCochain φ α β h = (↑(CochainComplex.mappingCone.fst φ)).comp α (_ : 1 + m = n) + (CochainComplex.mappingCone.snd φ).comp β (_ : 0 + n = n)
Instances For
Given φ : F ⟶ G
, this is the cocycle in Cocycle (mappingCone φ) K n
that is
constructed from α : Cochain F K m
(with m + 1 = n
) and β : Cocycle F K n
,
when a suitable cocycle relation is satisfied.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given φ : F ⟶ G
, this is the morphism mappingCone φ ⟶ K
that is constructed
from a cochain α : Cochain F K (-1)
and a morphism β : G ⟶ K
such that
δ (-1) 0 α = Cochain.ofHom (φ ≫ β)
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Constructor for homotopies between morphisms from a mapping cone.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given φ : F ⟶ G
, this is the cochain in Cochain (mappingCone φ) K n
that is
constructed from two cochains α : Cochain F K m
(with m + 1 = n
) and β : Cochain F K n
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given φ : F ⟶ G
, this is the cocycle in Cocycle K (mappingCone φ) n
that is
constructed from α : Cochain K F m
(with n + 1 = m
) and β : Cocycle K G n
,
when a suitable cocycle relation is satisfied.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given φ : F ⟶ G
, this is the morphism K ⟶ mappingCone φ
that is constructed
from a cocycle α : Cochain K F 1
and a cochain β : Cochain K G 0
when a suitable cocycle relation is satisfied.
Equations
Instances For
Constructor for homotopies between morphisms to a mapping cone.
Equations
- One or more equations did not get rendered due to their size.