The left and right unitors #
Given a bifunctor F : C ⥤ D ⥤ D
, an object X : C
such that F.obj X ≅ 𝟭 D
and a
map p : I × J → J
such that hp : ∀ (j : J), p ⟨0, j⟩ = j
,
we define an isomorphism of J
-graded objects for any Y : GradedObject J D
.
mapBifunctorLeftUnitor F X e p hp Y : mapBifunctorMapObj F p ((single₀ I).obj X) Y ≅ Y
.
Under similar assumptions, we also obtain a right unitor isomorphism
mapBifunctorMapObj F p X ((single₀ I).obj Y) ≅ X
. Finally,
the lemma mapBifunctor_triangle
promotes a triangle identity involving functors
to a triangle identity for the induced functors on graded objects.
Given F : C ⥤ D ⥤ D
, X : C
, e : F.obj X ≅ 𝟭 D
and Y : GradedObject J D
,
this is the isomorphism ((mapBifunctor F I J).obj ((single₀ I).obj X)).obj Y a ≅ Y a.2
when a : I × J
is such that a.1 = 0
.
Equations
- CategoryTheory.GradedObject.mapBifunctorObjSingle₀ObjIso F X e Y a ha = (F.mapIso (CategoryTheory.GradedObject.singleObjApplyIsoOfEq 0 X a.1 ha)).app (Y a.2) ≪≫ e.app (Y a.2)
Instances For
Given F : C ⥤ D ⥤ D
, X : C
and Y : GradedObject J D
,
((mapBifunctor F I J).obj ((single₀ I).obj X)).obj Y a
is an initial object
when a : I × J
is such that a.1 ≠ 0
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given F : C ⥤ D ⥤ D
, X : C
, e : F.obj X ≅ 𝟭 D
, Y : GradedObject J D
and
p : I × J → J
such that p ⟨0, j⟩ = j
for all j
,
this is the (colimit) cofan which shall be used to construct the isomorphism
mapBifunctorMapObj F p ((single₀ I).obj X) Y ≅ Y
, see mapBifunctorLeftUnitor
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The cofan mapBifunctorLeftUnitorCofan F X e p hp Y j
is a colimit.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given F : C ⥤ D ⥤ D
, X : C
, e : F.obj X ≅ 𝟭 D
, Y : GradedObject J D
and
p : I × J → J
such that p ⟨0, j⟩ = j
for all j
,
this is the left unitor isomorphism mapBifunctorMapObj F p ((single₀ I).obj X) Y ≅ Y
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given F : D ⥤ C ⥤ D
, Y : C
, e : F.flip.obj X ≅ 𝟭 D
and X : GradedObject J D
,
this is the isomorphism ((mapBifunctor F J I).obj X).obj ((single₀ I).obj Y) a ≅ Y a.2
when a : J × I
is such that a.2 = 0
.
Equations
- CategoryTheory.GradedObject.mapBifunctorObjObjSingle₀Iso F Y e X a ha = (F.obj (X a.1)).mapIso (CategoryTheory.GradedObject.singleObjApplyIsoOfEq 0 Y a.2 ha) ≪≫ e.app (X a.1)
Instances For
Given F : D ⥤ C ⥤ D
, Y : C
and X : GradedObject J D
,
((mapBifunctor F J I).obj X).obj ((single₀ I).obj X) a
is an initial when a : J × I
is such that a.2 ≠ 0
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given F : D ⥤ C ⥤ D
, Y : C
, e : F.flip.obj Y ≅ 𝟭 D
, X : GradedObject J D
and
p : J × I → J
such that p ⟨j, 0⟩ = j
for all j
,
this is the (colimit) cofan which shall be used to construct the isomorphism
mapBifunctorMapObj F p X ((single₀ I).obj Y) ≅ X
, see mapBifunctorRightUnitor
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
The cofan mapBifunctorRightUnitorCofan F Y e p hp X j
is a colimit.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given F : D ⥤ C ⥤ D
, Y : C
, e : F.flip.obj Y ≅ 𝟭 D
, X : GradedObject J D
and
p : J × I → J
such that p ⟨j, 0⟩ = j
for all j
,
this is the right unitor isomorphism mapBifunctorMapObj F p X ((single₀ I).obj Y) ≅ X
.
Equations
- One or more equations did not get rendered due to their size.
Instances For
Given two maps r : I₁ × I₂ × I₃ → J
and π : I₁ × I₃ → J
, this structure is the
input in the formulation of the triangle equality mapBifunctor_triangle
which
relates the left and right unitor and the associator for GradedObject.mapBifunctor
.
- p₁₂ : I₁ × I₂ → I₁
a map
I₁ × I₂ → I₁
- p₂₃ : I₂ × I₃ → I₃
a map
I₂ × I₃ → I₃
- h₁ (i₁ : I₁) : self.p₁₂ (i₁, 0) = i₁
- h₃ (i₃ : I₃) : self.p₂₃ (0, i₃) = i₃
Instances For
The BifunctorComp₁₂IndexData r
attached to a TriangleIndexData r π
.
Equations
- τ.ρ₁₂ = { I₁₂ := I₁, p := τ.p₁₂, q := π, hpq := ⋯ }
Instances For
The BifunctorComp₂₃IndexData r
attached to a TriangleIndexData r π
.
Equations
- τ.ρ₂₃ = { I₂₃ := I₃, p := τ.p₂₃, q := π, hpq := ⋯ }