OAI/Analysis/KadisonSimilarity/FreeProduct/ReducedWordAutomorphisms.lean
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.
- theorem
OAI.KadisonSimilarity.TracialCornerGeometry.reducedWord_mem_factorAlgebraline 18Source 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
- theorem
OAI.KadisonSimilarity.TracialCornerGeometry.factorsTraciallyGenerate_of_reducedWordGeneratedline 45Source 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 … - def
OAI.KadisonSimilarity.TracialCornerGeometry.matrixAutomorphismOfReducedWordsline 67Source 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 := …