Multiplicative bases

MultiplicativeBasisDeformations.Foundations.Descent

Proposition 4.14: descent of a multiplicative basis along a free deck group #

prop:scalar-normalization (scalar-normalization.tex): "Let b_{xy} be the multiplicative basis constructed on L. For a free deck generator g, write g(b_{xy}) = d_g(x, y) b_{gx,gy}. The coefficients form a multiplicative weight. By Lemma 4.13, write d_g(x, y) = a_g(y)/a_g(x). On each orbit of objects solve f(gx) = a_g(x) f(x) for all free generators. The orbit graph is a Cayley tree, so a value at one root determines consistent values everywhere. Then b'_{xy} = (f(y)/f(x)) b_{xy} is still multiplicative and is deck invariant."

For a graded family with a thin cover, a multiplicative basis β on the cover, a free grading group, and Lemma 4.13 as a hypothesis (hratio), we build the deck-invariant multiplicative basis b' (invBasis). The deck group acts on the cover by translating sheets (tr), with the same morphisms (trHom). The values f are the transport of (root, 1) under the homomorphism from the free group to permutations of objects × kˣ lifting the generators (Ψ): this is "a value at one root determines consistent values everywhere".

Deck translations of the cover #

def MultiplicativeBasisDeformations.CatAlg.tr {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) (o : CovObj D) :

Translation of the sheet by g.

Instances For
    @[simp]
    theorem MultiplicativeBasisDeformations.CatAlg.tr_fst {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) (o : CovObj D) :
    (tr g o).1 = o.1
    @[simp]
    theorem MultiplicativeBasisDeformations.CatAlg.tr_snd {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) (o : CovObj D) :
    (tr g o).2 = g * o.2
    theorem MultiplicativeBasisDeformations.CatAlg.tr_mul {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g h : G) (o : CovObj D) :
    tr (g * h) o = tr g (tr h o)
    theorem MultiplicativeBasisDeformations.CatAlg.tr_one {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (o : CovObj D) :
    tr 1 o = o
    theorem MultiplicativeBasisDeformations.CatAlg.tr_inv_tr {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) (o : CovObj D) :
    tr g⁻¹ (tr g o) = o
    theorem MultiplicativeBasisDeformations.CatAlg.tr_tr_inv {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) (o : CovObj D) :
    tr g (tr g⁻¹ o) = o
    theorem MultiplicativeBasisDeformations.CatAlg.tr_part {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) (o o' : CovObj D) :
    CovHom (tr g o) (tr g o') = CovHom o o'
    def MultiplicativeBasisDeformations.CatAlg.trHom {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) {o o' : CovObj D} (f : o ⟶ o') :
    tr g o ⟶ tr g o'

    The translated morphism (the same morphism of the family).

    Instances For
      @[simp]
      theorem MultiplicativeBasisDeformations.CatAlg.trHom_val {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) {o o' : CovObj D} (f : o ⟶ o') :
      ↑(trHom g f) = ↑f
      theorem MultiplicativeBasisDeformations.CatAlg.trHom_comp {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) {o o' o'' : CovObj D} (f : o ⟶ o') (f' : o' ⟶ o'') :
      trHom g (CategoryTheory.CategoryStruct.comp f f') = CategoryTheory.CategoryStruct.comp (trHom g f) (trHom g f')
      theorem MultiplicativeBasisDeformations.CatAlg.trHom_smul {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) {o o' : CovObj D} (c : k) (f : o ⟶ o') :
      trHom g (c • f) = c • trHom g f
      theorem MultiplicativeBasisDeformations.CatAlg.trHom_ne_zero {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) {o o' : CovObj D} {f : o ⟶ o'} (hf : f ≠ 0) :
      trHom g f ≠ 0
      def MultiplicativeBasisDeformations.CatAlg.untrHom {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (g : G) {o o' : CovObj D} (f : tr g o ⟶ tr g o') :
      o ⟶ o'

      Morphisms back from the translated objects.

      Instances For

        The weights d_g #

        theorem MultiplicativeBasisDeformations.CatAlg.β_ne_zero_iff {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) {o o' : CovObj D} :
        β o o' ≠ 0 ↔ ∃ (f : o ⟶ o'), f ≠ 0
        noncomputable def MultiplicativeBasisDeformations.CatAlg.dg {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) (β : (o o' : CovObj D) → o ⟶ o') (g : G) (o o' : CovObj D) :
        k

        The coefficients of a deck translation: g(b_{xy}) = d_g(x, y) b_{gx,gy}.

        Instances For
          theorem MultiplicativeBasisDeformations.CatAlg.dg_spec {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) (g : G) {o o' : CovObj D} (h : β o o' ≠ 0) :
          trHom g (β o o') = dg hT β g o o' • β (tr g o) (tr g o')
          theorem MultiplicativeBasisDeformations.CatAlg.dg_isWeight {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) (g : G) :
          Thin.IsWeight Set.univ (dg hT β g)

          The coefficients form a multiplicative weight.

          Object values on the orbits #

          theorem MultiplicativeBasisDeformations.CatAlg.exists_aG {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (g : G) :
          ∃ (a : CovObj D → k), (∀ (o : CovObj D), a o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → dg hT β g o o' = a o' / a o

          Lemma 4.13 applied to d_g: d_g(x, y) = a_g(y)/a_g(x).

          noncomputable def MultiplicativeBasisDeformations.CatAlg.aG {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (g : G) (o : CovObj D) :
          kˣ

          The values a_g.

          Instances For
            theorem MultiplicativeBasisDeformations.CatAlg.aG_spec {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (g : G) {o o' : CovObj D} (h : β o o' ≠ 0) :
            dg hT β g o o' = ↑(aG hT hβ hratio g o') / ↑(aG hT hβ hratio g o)
            noncomputable def MultiplicativeBasisDeformations.CatAlg.πs {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (a : IsFreeGroup.Generators G) :
            Equiv.Perm (CovObj D × kˣ)

            The permutation of objects × kˣ lifting a free generator: (o, λ) ↦ (g o, a_g(o) λ).

            Instances For
              noncomputable def MultiplicativeBasisDeformations.CatAlg.Ψd {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) :
              G →* Equiv.Perm (CovObj D × kˣ)

              The lift to the free group.

              Instances For
                def MultiplicativeBasisDeformations.CatAlg.HasForm {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (σ : Equiv.Perm (CovObj D × kˣ)) (g : G) :

                The transports have the form (o, λ) ↦ (g o, c(o) λ).

                Instances For
                  theorem MultiplicativeBasisDeformations.CatAlg.hasForm_mul {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} [IsFreeGroup G] {σ τ : Equiv.Perm (CovObj D × kˣ)} {g h : G} (hσ : HasForm σ g) (hτ : HasForm τ h) :
                  HasForm (σ * τ) (g * h)
                  theorem MultiplicativeBasisDeformations.CatAlg.hasForm_inv {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} [IsFreeGroup G] {σ : Equiv.Perm (CovObj D × kˣ)} {g : G} (hσ : HasForm σ g) :
                  HasForm σ⁻¹ g⁻¹
                  theorem MultiplicativeBasisDeformations.CatAlg.free_induction {G : Type} [Group G] [DecidableEq G] [IsFreeGroup G] {P : G → Prop} (h1 : P 1) (hof : ∀ (a : IsFreeGroup.Generators G), P (IsFreeGroup.of a)) (hmul : ∀ (g h : G), P g → P h → P (g * h)) (hinv : ∀ (g : G), P g → P g⁻¹) (g : G) :
                  P g

                  Induction over a free group.

                  theorem MultiplicativeBasisDeformations.CatAlg.Ψd_form {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (g : G) :
                  HasForm ((Ψd hT hβ hratio) g) g
                  def MultiplicativeBasisDeformations.CatAlg.root {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (o : CovObj D) :

                  The root of the orbit of o.

                  Instances For
                    theorem MultiplicativeBasisDeformations.CatAlg.tr_root {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} [IsFreeGroup G] (o : CovObj D) :
                    tr o.2 (root o) = o
                    noncomputable def MultiplicativeBasisDeformations.CatAlg.fv {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (o : CovObj D) :
                    kˣ

                    The object values f: the transport of (root, 1).

                    Instances For
                      theorem MultiplicativeBasisDeformations.CatAlg.Ψd_root {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (o : CovObj D) :
                      ((Ψd hT hβ hratio) o.2) (root o, 1) = (o, fv hT hβ hratio o)
                      theorem MultiplicativeBasisDeformations.CatAlg.fv_tr {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (a : IsFreeGroup.Generators G) (o : CovObj D) :
                      fv hT hβ hratio (tr (IsFreeGroup.of a) o) = aG hT hβ hratio (IsFreeGroup.of a) o * fv hT hβ hratio o

                      f(g x) = a_g(x) f(x) for the free generators.

                      The invariant basis #

                      noncomputable def MultiplicativeBasisDeformations.CatAlg.bInv {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (o o' : CovObj D) :
                      o ⟶ o'

                      b'_{xy} = (f(y)/f(x)) b_{xy}.

                      Instances For
                        def MultiplicativeBasisDeformations.CatAlg.pt {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (x : ι) (g : G) :

                        The object (x, g) of the cover.

                        Instances For
                          @[simp]
                          theorem MultiplicativeBasisDeformations.CatAlg.pt_fst {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} [IsFreeGroup G] (x : ι) (g : G) :
                          (pt x g).1 = x
                          @[simp]
                          theorem MultiplicativeBasisDeformations.CatAlg.pt_snd {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} [IsFreeGroup G] (x : ι) (g : G) :
                          (pt x g).2 = g
                          theorem MultiplicativeBasisDeformations.CatAlg.bInv_sheet {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) {x y : ι} {g g' h h' : G} (hg : g = g') (hh : h = h') :
                          ↑(bInv hT hβ hratio (pt x g) (pt y h)) = ↑(bInv hT hβ hratio (pt x g') (pt y h'))
                          theorem MultiplicativeBasisDeformations.CatAlg.bInv_mul {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (o o' o'' : CovObj D) :
                          CategoryTheory.CategoryStruct.comp (bInv hT hβ hratio o o') (bInv hT hβ hratio o' o'') = 0 ∨ CategoryTheory.CategoryStruct.comp (bInv hT hβ hratio o o') (bInv hT hβ hratio o' o'') = bInv hT hβ hratio o o''

                          b' is still multiplicative.

                          theorem MultiplicativeBasisDeformations.CatAlg.bInv_id {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (o : CovObj D) :
                          bInv hT hβ hratio o o = CategoryTheory.CategoryStruct.id o
                          theorem MultiplicativeBasisDeformations.CatAlg.bInv_ne_zero {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) {o o' : CovObj D} (h : β o o' ≠ 0) :
                          bInv hT hβ hratio o o' ≠ 0
                          theorem MultiplicativeBasisDeformations.CatAlg.bInv_tr_of {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (a : IsFreeGroup.Generators G) (o o' : CovObj D) :
                          ↑(bInv hT hβ hratio (tr (IsFreeGroup.of a) o) (tr (IsFreeGroup.of a) o')) = ↑(bInv hT hβ hratio o o')

                          b' is invariant under the free generators.

                          theorem MultiplicativeBasisDeformations.CatAlg.bInv_tr {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (g : G) (o o' : CovObj D) :
                          ↑(bInv hT hβ hratio (tr g o) (tr g o')) = ↑(bInv hT hβ hratio o o')

                          b' is deck invariant.

                          Descent #

                          noncomputable def MultiplicativeBasisDeformations.CatAlg.bD {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (x y : ι) (g : G) :
                          F x ⟶ F y

                          The descended vectors: b(x, y, g) = b'_{(x,1),(y,g)}.

                          Instances For
                            theorem MultiplicativeBasisDeformations.CatAlg.bD_mem {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (x y : ι) (g : G) :
                            bD hT hβ hratio x y g ∈ D.part g x y
                            theorem MultiplicativeBasisDeformations.CatAlg.bD_ne_zero {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) {x y : ι} {g : G} (h : D.part g x y ≠ ⊥) :
                            bD hT hβ hratio x y g ≠ 0
                            theorem MultiplicativeBasisDeformations.CatAlg.bD_span {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) {x y : ι} {g : G} {f : F x ⟶ F y} (hf : f ∈ D.part g x y) :
                            ∃ (c : k), f = c • bD hT hβ hratio x y g
                            theorem MultiplicativeBasisDeformations.CatAlg.bD_id {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (x : ι) :
                            bD hT hβ hratio x x 1 = CategoryTheory.CategoryStruct.id (F x)
                            theorem MultiplicativeBasisDeformations.CatAlg.bD_mul {k : Type u} [Field k] {𝒞 : Type v} [CategoryTheory.Category.{u, v} 𝒞] [CategoryTheory.Preadditive 𝒞] [CategoryTheory.Linear k 𝒞] {ι : Type} [Fintype ι] [DecidableEq ι] {F : ι → 𝒞} {G : Type} [Group G] [DecidableEq G] {D : HomGrading F G} (hT : Thin.IsThin k (CovObj D)) {β : (o o' : CovObj D) → o ⟶ o'} (hβ : Thin.MultBasis Set.univ β) [IsFreeGroup G] (hratio : ∀ (d : CovObj D → CovObj D → k), Thin.IsWeight Set.univ d → ∃ (ζ : CovObj D → k), (∀ (o : CovObj D), ζ o ≠ 0) ∧ ∀ (o o' : CovObj D) (f : o ⟶ o'), f ≠ 0 → d o o' = ζ o' / ζ o) (x y z : ι) (g h : G) :
                            CategoryTheory.CategoryStruct.comp (bD hT hβ hratio x y g) (bD hT hβ hratio y z h) = 0 ∨ CategoryTheory.CategoryStruct.comp (bD hT hβ hratio x y g) (bD hT hβ hratio y z h) = bD hT hβ hratio x z (g * h)

                            The descended vectors are multiplicative.