Kupisch uniseriality for selected projectives #
The primitive-corner finite-ideal theorem gives comparability on literal corners. This file transports it through the fully faithful coordinate functor to the selected-projective category and applies the generic Kupisch classification, producing condition (K)(2) in the exact module orientation used by the Skowroński--Waschbüsch correction.
theorem
MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.PrimitiveProjectivePresentation.finiteIdeal_projectiveHom_homSubbimodule_comparable
{k A : Type u}
[Field k]
[Ring A]
[Algebra k A]
[FiniteDimensional k A]
[IsNoetherianRing Aᵐᵒᵖ]
{S : FiniteIndecomposableSkeleton k A}
[IsAlgClosed k]
(P : S.PrimitiveProjectivePresentation)
(hA : IsRepresentationFinite k A)
{X Y : S.ProjectiveCategory}
(T U : Submodule k (X ⟶ Y))
(hT : IsHomSubbimodule T)
(hU : IsHomSubbimodule U)
:
T ≤ U ∨ U ≤ T
Representation-finite primitive-corner comparability transported to the literal selected-projective category.
theorem
MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.PrimitiveProjectivePresentation.finiteIdeal_projectiveHom_uniserialAlternative
{k A : Type u}
[Field k]
[Ring A]
[Algebra k A]
[FiniteDimensional k A]
[IsNoetherianRing Aᵐᵒᵖ]
{S : FiniteIndecomposableSkeleton k A}
[IsAlgClosed k]
(P : S.PrimitiveProjectivePresentation)
(hA : IsRepresentationFinite k A)
(X Y : S.ProjectiveCategory)
:
IsUniserialModule (CategoryTheory.End Y) (X ⟶ Y) ∨ IsUniserialModule (CategoryTheory.End X)ᵐᵒᵖ (X ⟶ Y)
Representation-finiteness gives Kupisch's exact target-side or opposite-source-side uniserial alternative on every selected-projective Hom space.