Presentation-level reverse comparison naturality #
theorem
MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.finiteCovariantDefectPresentationLinearEquiv_representable_precomp
{k A : Type u}
[Field k]
[IsAlgClosed k]
[Ring A]
[Algebra k A]
[FiniteDimensional k A]
[IsNoetherianRing Aᵐᵒᵖ]
(S : FiniteIndecomposableSkeleton k A)
[CategoryTheory.HasExt S.FiniteCovariantFunctor]
{K : CategoryTheory.ShortComplex FG}
(hK : K.ShortExact)
{X Y : S.IndecCategoryᵒᵖ}
(a : X ⟶ Y)
(f : (S.fgObj (Opposite.unop X)).obj ⟶ K.X₃.obj)
:
(S.finiteCovariantDefectPresentationLinearEquiv hK Y)
(Submodule.Quotient.mk
(S.finiteRestrictedCovariantRepresentableMap
(CategoryTheory.ObjectProperty.homMk (CategoryTheory.CategoryStruct.comp (S.fgMap a.unop).hom f)))) = ((CategoryTheory.Abelian.Ext.mk₀ (S.finiteCovariantRepresentableOnSkeleton.map a)).postcompOfLinear k
(S.finiteCovariantDefect K) ⋯)
((S.finiteCovariantDefectPresentationLinearEquiv hK X)
(Submodule.Quotient.mk (S.finiteRestrictedCovariantRepresentableMap (CategoryTheory.ObjectProperty.homMk f))))
Naturality of the reverse Ext² comparison on quotient representatives coming from restricted covariant Yoneda.