OAI/Analysis/PureInfiniteness/CentralSequenceAbsorption.lean

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4 declarations, 0 contain sorry, 0 declared as axioms

Absorption from the published central-sequence embedding

The embedding below is into (Aω ∩ A') / Ann(A, Aω). This is the central-sequence embedding immediately preceding Proposition 4.4 in Kirchberg, Central sequences in C-algebras and strongly purely infinite algebras*, Abel Symposia 1 (2006), 175--231. The structural hypotheses specialize Proposition 4.4(1),(3),(5) and Remark 4.6 to the absorbing algebra: nuclearity, simplicity, and a connected approximate half-flip in a faithful C*-completion of its algebraic tensor square. Tensor absorption follows from quotient intertwining.

  1. lemma OAI.WeakPureInfiniteness.tensorMultiplier_polynomial_mem line 30
  2. lemma OAI.WeakPureInfiniteness.tensorMultiplier_coefficient_dense line 47
  3. theorem OAI.WeakPureInfiniteness.minimalTensor_equiv_of_central_embedding line 69

    Source documentation

    The nonunital tensor absorption argument from an actual central embedding.

    theorem minimalTensor_equiv_of_central_embedding
        (U : Ultrafilter ℕ) [Fact ((U : Filter ℕ) ≤ atTop)]
        (φ : D →⋆ₐ[ℂ] NonunitalGamma.CentralSequenceAlgebra (A := A) U)
    …

    Mentions: OAI.NonunitalGamma.CentralSequenceAlgebra

  4. theorem OAI.WeakPureInfiniteness.Campaign.nuclear_absorption_from_published_inputs line 109

    Source documentation

    Corollary 1.3 from the separate published central-embedding and connected-half-flip inputs, including the zero algebra. No absorption proposition is a premise.

    theorem nuclear_absorption_from_published_inputs
        (U : Ultrafilter ℕ) [Fact ((U : Filter ℕ) ≤ atTop)]
        (hcentral : Nontrivial A → Nuclear A → StronglyPurelyInfinite A →
          Nonempty (OInfinity →⋆ₐ[ℂ]
            NonunitalGamma.CentralSequenceAlgebra (A := A) U))
    …

    Mentions: OAI.WeakPureInfiniteness.Nuclear, OAI.WeakPureInfiniteness.StronglyPurelyInfinite, OAI.WeakPureInfiniteness.OInfinity, OAI.NonunitalGamma.CentralSequenceAlgebra