Magnitude conjecture

MagnitudeConjecture.Algebra.RightModuleCoherentDefectEvaluation

Evaluating the covariant defect #

Evaluation is exact on the finite linear functor category. Consequently the value of the covariant defect at X is the ordinary quotient

Hom(A, X) / im(Hom(B, X) → Hom(A, X))

attached to the first map A → B of the module complex.

@[reducible, inline]
Instances For
    def MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.finiteCovariantFunctorInclusion {k A : Type u} [Field k] [Ring A] [Algebra k A] (S : FiniteIndecomposableSkeleton k A) :
    CategoryTheory.Functor S.FiniteCovariantFunctor (CategoryTheory.Functor S.IndecCategory (ModuleCat k))

    Forget the finite-dimensional and linear-property wrappers.

    Instances For
      def MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.finiteCovariantFunctorEvaluation {k A : Type u} [Field k] [Ring A] [Algebra k A] (S : FiniteIndecomposableSkeleton k A) (X : S.IndecCategory) :
      CategoryTheory.Functor S.FiniteCovariantFunctor (ModuleCat k)

      Evaluation of a finite covariant functor at a chosen indecomposable.

      Instances For
        @[reducible, inline]
        abbrev MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.finiteCovariantPresentationRange {k A : Type u} [Field k] [Ring A] [Algebra k A] (S : FiniteIndecomposableSkeleton k A) (K : CategoryTheory.ShortComplex FG) (X : S.IndecCategory) :
        Submodule k (K.X₁.obj ⟶ (S.fgObj X).obj)

        The ambient module-theoretic presentation coboundaries obtained by precomposing with the first map of K.

        Instances For
          theorem MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.finiteCovariantFunctorEvaluation_map_range {k A : Type u} [Field k] [Ring A] [Algebra k A] [FiniteDimensional k A] [IsNoetherianRing Aᵐᵒᵖ] (S : FiniteIndecomposableSkeleton k A) (K : CategoryTheory.ShortComplex FG) (X : S.IndecCategory) :

          Evaluating the covariant representable map gives the ordinary precomposition map in the module category.

          noncomputable def MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.finiteCovariantDefectEvaluationIsoPresentationQuotient {k A : Type u} [Field k] [Ring A] [Algebra k A] [FiniteDimensional k A] [IsNoetherianRing Aᵐᵒᵖ] (S : FiniteIndecomposableSkeleton k A) (K : CategoryTheory.ShortComplex FG) (X : S.IndecCategory) :
          (S.finiteCovariantDefect K).obj.obj.obj X ≅ ModuleCat.of k ((K.X₁.obj ⟶ (S.fgObj X).obj) ⧸ S.finiteCovariantPresentationRange K X)

          The value of the covariant defect is the module-presentation quotient.

          Instances For
            noncomputable def MagnitudeConjecture.RightModule.FiniteIndecomposableSkeleton.finiteCovariantDefectEvaluationLinearEquivPresentationQuotient {k A : Type u} [Field k] [Ring A] [Algebra k A] [FiniteDimensional k A] [IsNoetherianRing Aᵐᵒᵖ] (S : FiniteIndecomposableSkeleton k A) (K : CategoryTheory.ShortComplex FG) (X : S.IndecCategory) :
            ↑((S.finiteCovariantDefect K).obj.obj.obj X) ≃ₗ[k] (K.X₁.obj ⟶ (S.fgObj X).obj) ⧸ S.finiteCovariantPresentationRange K X

            Linear-equivalence form of the evaluated covariant-defect calculation.

            Instances For