English
The counit isomorphism provides the inverse direction as a natural equivalence between the two cone categories.
Русский
Изоморфизм counit обеспечивает обратное направление как естественное равнообразие между двумя категориями конусов.
LaTeX
$$$\mathrm{coneEquivCounitIso}(F,U) : \mathrm{Cone}\!\left((\mathrm{diagram} U)^{op} \circ F\right) \cong \mathrm{Cone}(\mathrm{TopCatPresheafSheafConditionEqualizerProductsDiagram}(F,U))$$$
Lean4
/-- Implementation of `SheafConditionPairwiseIntersections.coneEquiv`. -/
@[simps!]
def coneEquivCounitIso :
coneEquivInverse F U ⋙ coneEquivFunctor F U ≅ 𝟭 (Limits.Cone (SheafConditionEqualizerProducts.diagram F U)) :=
NatIso.ofComponents
(fun c =>
{ hom :=
{ hom := 𝟙 _
w := by
rintro ⟨_ | _⟩
· dsimp
ext
simp
· dsimp
ext
simp }
inv :=
{ hom := 𝟙 _
w := by
rintro ⟨_ | _⟩
· dsimp
ext
simp
· dsimp
ext
simp } })
fun {c d} f => by
ext
dsimp
simp only [Category.comp_id, Category.id_comp]