English
A variant of the prior compatibility statement written in terms of the pullbackHom comparison.
Русский
Вариант совместимости вышеописанного равенства, записанный через сравнение pullbackHom.
LaTeX
$$$$ (\mathcal{U}.pullbackCoverAffineRefinementObjIso f 𝒰 i)^{-1} \\circ (\mathcal{U}.C... \\text{(детали опущены)} $$$$
Lean4
@[reassoc]
theorem pullbackCoverAffineRefinementObjIso_inv_pullbackHom (f : X ⟶ Y) (𝒰 : Y.OpenCover) (i) :
(𝒰.pullbackCoverAffineRefinementObjIso f i).inv ≫ 𝒰.affineRefinement.openCover.pullbackHom f i =
(𝒰.X i.1).affineCover.pullbackHom (𝒰.pullbackHom f i.1) i.2 :=
by
simp only [Precoverage.ZeroHypercover.pullback₁_toPreZeroHypercover, PreZeroHypercover.pullback₁_X, Cover.pullbackHom,
AffineOpenCover.openCover_X, AffineOpenCover.openCover_f, pullbackCoverAffineRefinementObjIso, Iso.trans_inv,
asIso_inv, Iso.symm_inv, Category.assoc, pullbackSymmetry_inv_comp_snd, IsIso.inv_comp_eq, limit.lift_π,
PullbackCone.mk_pt, PullbackCone.mk_π_app, Category.comp_id]
convert pullbackSymmetry_inv_comp_fst ((𝒰.X i.1).affineCover.f i.2) (pullback.fst _ _)
exact pullbackRightPullbackFstIso_hom_fst _ _ _