OAI/Analysis/KadisonSimilarity/FreeProduct/ReducedWordAutomorphisms.lean

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3 declarations, 0 contain sorry, 0 declared as axioms

Dense reduced words provide the tracial generation needed to turn published factor embeddings into actual free-product automorphisms.

  1. theorem OAI.KadisonSimilarity.TracialCornerGeometry.reducedWord_mem_factorAlgebra line 18

    Source documentation

    Every bounded reduced word belongs to the algebra generated by the factors.

    theorem reducedWord_mem_factorAlgebra (n : ℕ) (d : D) (b : A)
        (a : Fin n → A) (c : Fin n → D) :
        (d : P) * alternatingProduct (fun i => (a i : P)) (fun i => (c i : P)) * (b : P) ∈
          factorAlgebra A D := by
    …

    Mentions: OAI.KadisonSimilarity.alternatingProduct, OAI.KadisonSimilarity.TracialCornerGeometry.factorAlgebra

  2. theorem OAI.KadisonSimilarity.TracialCornerGeometry.factorsTraciallyGenerate_of_reducedWordGenerated line 45

    Source documentation

    The ordinary reduced-word density supplies the tracial algebraic generation; no separate factor-generation hypothesis is required for automorphism extension.

    theorem factorsTraciallyGenerate_of_reducedWordGenerated
        (hgen : ReducedWordGenerated G A D) : G.FactorsTraciallyGenerate A D := by
    …

    Mentions: OAI.KadisonSimilarity.ReducedWordGenerated

  3. def OAI.KadisonSimilarity.TracialCornerGeometry.matrixAutomorphismOfReducedWords line 67

    Source documentation

    Existence of the ambient matrix-conjugation automorphism follows from the published two-factor extension and the actual reduced-word density.

    def matrixAutomorphismOfReducedWords
        (hgen : ReducedWordGenerated G A D) (hfaithful : Function.Injective G.vector)
        {α : Type*} [Fintype α] [DecidableEq α]
        (ι : Matrix α α ℂ →⋆ₐ[ℂ] D) (hext : G.MatrixConjugationExtensionInput D ι A)
        (u : Matrix.unitaryGroup α ℂ) : P ≃⋆ₐ[ℂ] P :=
    …

    Mentions: OAI.KadisonSimilarity.ReducedWordGenerated