OAI/Analysis/KadisonKastler/TomiyamaDenseProjections.lean

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2 declarations, 0 contain sorry, 0 declared as axioms

Extension from projections to their norm-closed span

  1. theorem OAI.KadisonKastler.closed_projection_span_eq_top_of_surjective line 16

    Source documentation

    A surjective star homomorphism preserves norm-density of projection spans.

    theorem closed_projection_span_eq_top_of_surjective
        (φ : A →⋆ₐ[ℂ] B) (hφ : Function.Surjective φ)
        (hdense : (Submodule.span ℂ {e : A | IsStarProjection e}).topologicalClosure = ⊤) :
        (Submodule.span ℂ {e : B | IsStarProjection e}).topologicalClosure = ⊤ := by
    …
  2. theorem OAI.KadisonKastler.tomiyama_map_mul_of_dense_projections line 38

    Source documentation

    The algebraic projection identities extend to a target whose projections have norm-dense linear span.

    theorem tomiyama_map_mul_of_dense_projections
        (hdense : (Submodule.span ℂ {e : B | IsStarProjection e}).topologicalClosure = ⊤)
        (φ : B →⋆ₐ[ℂ] A) (P : A →L[ℂ] B)
        (hP : ∀ x, ‖P x‖ ≤ ‖x‖) (hfix : ∀ b, P (φ b) = b) :
        (∀ b x, P (φ b * x) = b * P x) ∧ (∀ x b, P (x * φ b) = P x * b) := by
    …