English
There is a unit isomorphism for the equivalence between cones over the pairwise diagram and cones over the equalizer diagram.
Русский
Существует модуль единичного изоморфизма для эквивалентности конусов между диаграммой Pairwise и диаграммой равносилки.
LaTeX
$$$\mathrm{coneEquivUnitIso}(F,U) : \mathbf{1} \to (\mathrm{coneEquivFunctor}(F,U) \circ \mathrm{coneEquivInverse}(F,U))$$$
Lean4
/-- Implementation of `SheafConditionPairwiseIntersections.coneEquiv`. -/
@[simps!]
def coneEquivInverse : Limits.Cone (SheafConditionEqualizerProducts.diagram F U) ⥤ Limits.Cone ((diagram U).op ⋙ F)
where
obj c := coneEquivInverseObj F U c
map {c c'}
f :=
{ hom := f.hom
w := by
intro x
induction x with
| op x => ?_
rcases x with (⟨i⟩ | ⟨i, j⟩)
· dsimp
dsimp only [Fork.ι]
rw [← f.w WalkingParallelPair.zero, Category.assoc]
· dsimp
rw [← f.w WalkingParallelPair.one, Category.assoc] }