OAI/Analysis/KadisonSimilarity/Representation/CountableProjectionJoin.lean

GitHub source file

9 declarations, 0 contain sorry, 0 declared as axioms

Countable projection joins with the trace bound inherited from finite unions. Only the concrete faithful vector trace is used for the limit.

  1. def OAI.KadisonSimilarity.finiteProjectionJoin line 21
  2. theorem OAI.KadisonSimilarity.finiteProjectionJoin_isStarProjection line 26
  3. theorem OAI.KadisonSimilarity.finiteProjectionJoin_step line 33
  4. theorem OAI.KadisonSimilarity.finiteProjectionJoin_contains line 39
  5. theorem OAI.KadisonSimilarity.finiteProjectionJoin_mono line 57
  6. theorem OAI.KadisonSimilarity.finiteProjectionJoin_least line 71
  7. theorem OAI.KadisonSimilarity.trace_finiteProjectionJoin_le line 80
  8. theorem OAI.KadisonSimilarity.exists_countable_projection_join line 93

    Source documentation

    The join has trace bounded by every common bound on finite trace sums.

    theorem exists_countable_projection_join (M : VonNeumannAlgebra H)
        (υ : TracialRepresentation M) (τ : M.toStarSubalgebra →ₚ[ℂ] ℂ)
        (hτ : ∀ a, τ a = υ.trace a)
        (p : ℕ → M.toStarSubalgebra) (hp : ∀ n, IsStarProjection (p n))
        (C : ℝ) (hC : ∀ n, ∑ i ∈ Finset.range n, (τ (p i)).re ≤ C) :
        ∃ q : M.toStarSubalgebra, IsStarProjection q ∧ (τ q).re ≤ C ∧
          (∀ n, q * p n = p n) ∧
          ∀ r : M.toStarSubalgebra, IsStarProjection r → (∀ n, r * p n = p n) → r * q = q := by
    …
  9. theorem OAI.KadisonSimilarity.exists_countable_projection_join_of_equiv line 123

    Source documentation

    The countable trace bound transports through a star isomorphism. Only the target trace needs to be presented by a concrete vector.

    theorem exists_countable_projection_join_of_equiv
        {K : Type*} [NormedAddCommGroup K] [InnerProductSpace ℂ K] [CompleteSpace K]
        (M : VonNeumannAlgebra H) (N : VonNeumannAlgebra K)
        [IsClosed (N.toStarSubalgebra : Set (K →L[ℂ] K))]
        (e : M.toStarSubalgebra ≃⋆ₐ[ℂ] N.toStarSubalgebra)
        (υ : TracialRepresentation N)
        (τ : M.toStarSubalgebra →ₚ[ℂ] ℂ) (σ : N.toStarSubalgebra →ₚ[ℂ] ℂ)
        (hσ : ∀ b, σ b = υ.trace b) (he : ∀ a, σ (e a) = τ a)
        (p : ℕ → M.toStarSubalgebra) (hp : ∀ n, IsStarProjection (p n))
        (C : ℝ) (hC : ∀ n, ∑ i ∈ Finset.range n, (τ (p i)).re ≤ C) :
        ∃ q : M.toStarSubalgebra, IsStarProjection q ∧ (τ q).re ≤ C ∧
          (∀ n, q * p n = p n) ∧
    …