Multiplicative bases

MultiplicativeBasisDeformations.Statements.PolynomialMesh

Proposition 12.8 for A₀ and for a representation-finite algebra #

prop:polynomial-mesh-comparison (deformation-refinements.tex): "Let m + Σ_{i∈I} t_i μ_i be an associative family satisfying the hypotheses of Proposition 7.9, such as eq. selected-binary-family, now indexed by I = I₀. There are polynomial lifts […] for which the retained mesh coefficients are F_i(t) = a_i t_i, a_i ∈ k^*. After every specialization to k, these modules exhaust the indecomposables of the fibre algebra."

In the setting of Proposition 7.9 (familyCriterion_A0): the rows R_i and dual mesh weights of Proposition 6.1 (rows of length at least three, the degree 2s + 2 of Proposition 6.1), the characters χ_i (rowChar), and a family μ_i indexed by all rows with the hypotheses of Proposition 7.9 (normalized relative, of character χ_i, not a coboundary, associative family). The internal degree len R_i − 2 of μ_i is derived from its character (RaySys.Sys.hasDeg₂_of_char), the coordinates χ_i ↦ e_i are the dual weights, and the generic polynomialMeshComparison applies (polynomialMeshComparison_A0); for A₀ of a representation-finite algebra the mesh hypotheses are the Auslander–Reiten ones (IndSkeleton.polynomialMeshComparison_ar).

The dual-weight coordinates ℤ^ι × ℤ → ℤ^ι.

Instances For
    theorem MultiplicativeBasisDeformations.MeshWalk.dualCoords_rowChar {V : Type} [Quiver V] [Fintype V] [DecidableEq V] {Q : TranslationQuiver V} [(x : V) → Fintype ((y : V) × (y ⟶ x))] [hone : ∀ (x y : V), Subsingleton (x ⟶ y)] [(x y : V) → Fintype (x ⟶ y)] {ι : Type} [Fintype ι] [DecidableEq ι] (Wd : ι → MeshWt Q ℤ) (Rw : ι → (x : ↑Q.nonprojective) × Quiver.Path ↑(Q.tau x) ↑x) (hWd : ∀ (i j : ι), rowWt (Wd i) (Rw j) = if j = i then 1 else 0) (i : ι) :
    dualCoords (rowChar Wd Rw i) = Pi.single i 1
    def MultiplicativeBasisDeformations.MeshWalk.PolyMeshStmt {k : Type u} [Field k] {V : Type} [Quiver V] [Fintype V] [DecidableEq V] {Q : TranslationQuiver V} [(x : V) → Fintype ((y : V) × (y ⟶ x))] {c : MeshCoefficients k Q} {L : CatAlg.LocalFamily (meshFam Q c)} (D : CatAlg.MeshData (meshFam Q c) L) [IsAlgClosed k] [hone : ∀ (x y : V), Subsingleton (x ⟶ y)] [(x y : V) → Fintype (x ⟶ y)] [hfd : ∀ (x y : V), FiniteDimensional k (meshFam Q c x ⟶ meshFam Q c y)] {ι : Type} [Fintype ι] [DecidableEq ι] (Wd : ι → MeshWt Q ℤ) (Rw : ι → (x : ↑Q.nonprojective) × Quiver.Path ↑(Q.tau x) ↑x) [Infinite k] (J : D.InjData) (h1 : DegOne D) [Fintype ↑Q.nonprojective] (μ : ι → (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ) :

    The conclusion of Proposition 12.8 for the family μ with the rows Rw and characters rowChar.

    Instances For
      theorem MultiplicativeBasisDeformations.MeshWalk.polynomialMeshComparison_A0 {k : Type u} [Field k] {V : Type} [Quiver V] [Fintype V] [DecidableEq V] {Q : TranslationQuiver V} [(x : V) → Fintype ((y : V) × (y ⟶ x))] {c : MeshCoefficients k Q} {L : CatAlg.LocalFamily (meshFam Q c)} (D : CatAlg.MeshData (meshFam Q c) L) [IsAlgClosed k] [hone : ∀ (x y : V), Subsingleton (x ⟶ y)] [(x y : V) → Fintype (x ⟶ y)] [hfd : ∀ (x y : V), FiniteDimensional k (meshFam Q c x ⟶ meshFam Q c y)] (v₀ : V) (hF : IsRepresentationFinite k (CatAlg.Alg D.F0)ᵐᵒᵖ) {ι : Type} [Fintype ι] [DecidableEq ι] (Wd : ι → MeshWt Q ℤ) (Rw : ι → (x : ↑Q.nonprojective) × Quiver.Path ↑(Q.tau x) ↑x) [Infinite k] (J : D.InjData) (h1 : DegOne D) [Fintype ↑Q.nonprojective] (hrad : ∀ (x y : V) (d : ℕ), 1 ≤ d → ∀ f ∈ ScalarMeshCategory.degreePart c d x y, f ∈ L.rad x y) (hWd : ∀ (i j : ι), rowWt (Wd i) (Rw j) = if j = i then 1 else 0) (hS : ScalarMeshCategory.CokerSpan c (Set.range Rw)) (hlen3 : ∀ (i : ι), 3 ≤ (Rw i).snd.length) (μ : ι → (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ) (hrel : ∀ (i : ι), LenGrading.IsRel₂ (VxA0 D v₀ hF Wd) (μ i)) (hchar : ∀ (i : ι), (latA0 (dualWt Wd) ⋯ D).Char₂ (rowChar Wd Rw i) (μ i)) (hnz : ∀ (i : ι), ¬∃ (f : (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ), μ i = LenGrading.cobdry k f) (hassoc : ∀ (t : ι → k) (a b z : (CatAlg.Alg D.F0)ᵐᵒᵖ), ((famMul D μ t) (((famMul D μ t) a) b)) z = ((famMul D μ t) a) (((famMul D μ t) b) z)) :
      PolyMeshStmt D Wd Rw J h1 μ

      Proposition 12.8 on A₀, in the setting of Proposition 7.9.

      Characters in any lattice #

      def MultiplicativeBasisDeformations.MeshWalk.PolyMeshStmtG {k : Type u} [Field k] {V : Type} [Quiver V] [Fintype V] [DecidableEq V] {Q : TranslationQuiver V} [(x : V) → Fintype ((y : V) × (y ⟶ x))] {c : MeshCoefficients k Q} {L : CatAlg.LocalFamily (meshFam Q c)} (D : CatAlg.MeshData (meshFam Q c) L) [IsAlgClosed k] [hone : ∀ (x y : V), Subsingleton (x ⟶ y)] [(x y : V) → Fintype (x ⟶ y)] [hfd : ∀ (x y : V), FiniteDimensional k (meshFam Q c x ⟶ meshFam Q c y)] {ι : Type} [Fintype ι] [DecidableEq ι] (Rw : ι → (x : ↑Q.nonprojective) × Quiver.Path ↑(Q.tau x) ↑x) [Infinite k] {Lt : Type} [AddCommGroup Lt] (W : MeshWt Q Lt) (coords : Lt →+ ι → ℤ) (J : D.InjData) (h1 : DegOne D) [Fintype ↑Q.nonprojective] (μ : ι → (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ) :

      The conclusion of Proposition 12.8 for the family μ with the rows Rw and characters rowChar.

      Instances For
        theorem MultiplicativeBasisDeformations.MeshWalk.polynomialMeshComparison_G {k : Type u} [Field k] {V : Type} [Quiver V] [Fintype V] [DecidableEq V] {Q : TranslationQuiver V} [(x : V) → Fintype ((y : V) × (y ⟶ x))] {c : MeshCoefficients k Q} {L : CatAlg.LocalFamily (meshFam Q c)} (D : CatAlg.MeshData (meshFam Q c) L) [IsAlgClosed k] [hone : ∀ (x y : V), Subsingleton (x ⟶ y)] [(x y : V) → Fintype (x ⟶ y)] [hfd : ∀ (x y : V), FiniteDimensional k (meshFam Q c x ⟶ meshFam Q c y)] (v₀ : V) (hF : IsRepresentationFinite k (CatAlg.Alg D.F0)ᵐᵒᵖ) {ι : Type} [Fintype ι] [DecidableEq ι] (Rw : ι → (x : ↑Q.nonprojective) × Quiver.Path ↑(Q.tau x) ↑x) [Infinite k] {Lt : Type} [AddCommGroup Lt] (W : MeshWt Q Lt) (dg : Lt →+ ℤ) (hdg : dg.comp (MeshWt.res c D W) = MeshWt.res c D lenW) (coords : Lt →+ ι → ℤ) (J : D.InjData) (h1 : DegOne D) [Fintype ↑Q.nonprojective] (hrad : ∀ (x y : V) (d : ℕ), 1 ≤ d → ∀ f ∈ ScalarMeshCategory.degreePart c d x y, f ∈ L.rad x y) (hco : ∀ (i : ι), coords (rowCharG W Rw i) = Pi.single i 1) (hS : ScalarMeshCategory.CokerSpan c (Set.range Rw)) (hlen3 : ∀ (i : ι), 3 ≤ (Rw i).snd.length) (hdgrow : ∀ (i : ι), dg (rowCharG W Rw i) = ↑(Rw i).snd.length - 2) (μ : ι → (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ) (hrel : ∀ (i : ι), LenGrading.IsRel₂ (VxG D v₀ hF W dg hdg) (μ i)) (hchar : ∀ (i : ι), (latA0 W ⋯ D).Char₂ (rowCharG W Rw i) (μ i)) (hnz : ∀ (i : ι), ¬∃ (f : (CatAlg.Alg D.F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg D.F0)ᵐᵒᵖ), μ i = LenGrading.cobdry k f) (hassoc : ∀ (t : ι → k) (a b z : (CatAlg.Alg D.F0)ᵐᵒᵖ), ((famMul D μ t) (((famMul D μ t) a) b)) z = ((famMul D μ t) a) (((famMul D μ t) b) z)) :
        PolyMeshStmtG D Rw W coords J h1 μ

        Proposition 12.8 on A₀, in the setting of Proposition 7.9.

        theorem MultiplicativeBasisDeformations.IndSkeleton.polynomialMeshComparison_ar {k A : Type u} [Field k] [IsAlgClosed k] [Ring A] [Algebra k A] [FiniteDimensional k A] [IsNoetherianRing Aᵐᵒᵖ] (S : IndSkeleton k A) (b : S.ArrowBases) (v₀ : S.ARVertex) {ι : Type} [Fintype ι] [DecidableEq ι] (Wd : ι → MeshWalk.MeshWt S.arTranslationQuiver ℤ) (Rw : ι → (x : ↑S.arTranslationQuiver.nonprojective) × Quiver.Path ↑(S.arTranslationQuiver.tau x) ↑x) :
        have hF := ⋯; (∀ (i j : ι), MeshWalk.rowWt (Wd i) (Rw j) = if j = i then 1 else 0) → ScalarMeshCategory.CokerSpan (S.arCoefficients b) (Set.range Rw) → (∀ (i : ι), 3 ≤ (Rw i).snd.length) → ∀ (μ : ι → (CatAlg.Alg (S.arMeshData b).F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg (S.arMeshData b).F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg (S.arMeshData b).F0)ᵐᵒᵖ), (∀ (i : ι), LenGrading.IsRel₂ (MeshWalk.VxA0 (S.arMeshData b) v₀ hF Wd) (μ i)) → (∀ (i : ι), (MeshWalk.latA0 (MeshWalk.dualWt Wd) ⋯ (S.arMeshData b)).Char₂ (MeshWalk.rowChar Wd Rw i) (μ i)) → (∀ (i : ι), ¬∃ (f : (CatAlg.Alg (S.arMeshData b).F0)ᵐᵒᵖ →ₗ[k] (CatAlg.Alg (S.arMeshData b).F0)ᵐᵒᵖ), μ i = LenGrading.cobdry k f) → (∀ (t : ι → k) (a b' z : (CatAlg.Alg (S.arMeshData b).F0)ᵐᵒᵖ), ((MeshWalk.famMul (S.arMeshData b) μ t) (((MeshWalk.famMul (S.arMeshData b) μ t) a) b')) z = ((MeshWalk.famMul (S.arMeshData b) μ t) a) (((MeshWalk.famMul (S.arMeshData b) μ t) b') z)) → MeshWalk.PolyMeshStmt (S.arMeshData b) Wd Rw (S.arInjData b) ⋯ μ

        Proposition 12.8 (prop:polynomial-mesh-comparison) for A₀ of a basic representation-finite algebra A: for the rows and dual weights of Proposition 6.1 and a family μ_i indexed by all rows with the hypotheses of Proposition 7.9, the conclusions of polynomialMeshComparison hold (polynomial lifts, retained mesh coefficients a_i t_i with a_i ≠ 0, the mesh presentation of every fibre, and exhaustion of its indecomposables).