OAI/Analysis/KadisonKastler/ReducingCommutantCorner.lean

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9 declarations, 0 contain sorry, 0 declared as axioms

The commutant on a reducing subspace is the represented corner

  1. theorem OAI.KadisonKastler.invariant_of_commutes_starProjection line 20

    Source documentation

    An operator commuting with the subspace projection preserves the subspace.

    theorem invariant_of_commutes_starProjection (T : H →L[ℂ] H)
        (hT : E.starProjection * T = T * E.starProjection) :
        ∀ x ∈ E, T x ∈ E := by
    …
  2. theorem OAI.KadisonKastler.cornerExtension_mul_reducing line 31
  3. theorem OAI.KadisonKastler.reducing_mul_cornerExtension line 43
  4. theorem OAI.KadisonKastler.commutes_corner_iff line 55
  5. def OAI.KadisonKastler.commutantReducingHom line 69

    Source documentation

    Restrict the original algebra to a subspace reduced by it.

    def commutantReducingHom (M : VonNeumannAlgebra H)
        (hE : E.starProjection ∈ M.commutant) :
        Algebra M →⋆ₐ[ℂ] (E →L[ℂ] E) :=
    …

    Mentions: OAI.KadisonKastler.Algebra

  6. theorem OAI.KadisonKastler.commutantReducingHom_apply line 76
  7. theorem OAI.KadisonKastler.commutant_reducingClosure line 82

    Source documentation

    The full commutant of the restricted algebra is exactly the corner of the original commutant, with extension by zero identifying operators.

    theorem commutant_reducingClosure (M : VonNeumannAlgebra H)
        (hE : E.starProjection ∈ M.commutant) :
        (generatedVonNeumannAlgebra (commutantReducingHom E M hE).range).commutant =
          representedCorner E M.commutant hE := by
    …

    Mentions: OAI.KadisonKastler.generatedVonNeumannAlgebra, OAI.KadisonKastler.commutantReducingHom, OAI.KadisonKastler.representedCorner

  8. theorem OAI.KadisonKastler.commutantReducingHom_injective line 113

    Source documentation

    Full central support of the reducing projection makes restriction faithful.

    theorem commutantReducingHom_injective (M : VonNeumannAlgebra H)
        (hE : E.starProjection ∈ M.commutant) (hE0 : E.starProjection ≠ 0)
        (hN : ScalarCenter M.commutant) :
        Function.Injective (commutantReducingHom E M hE) := by
    …

    Mentions: OAI.KadisonKastler.ScalarCenter, OAI.KadisonKastler.commutantReducingHom

  9. theorem OAI.KadisonKastler.commutantReducingHom_boundedWeakNormal line 143

    Source documentation

    Restriction preserves bounded weak-operator limits coefficientwise.

    theorem commutantReducingHom_boundedWeakNormal (M : VonNeumannAlgebra H)
        (hE : E.starProjection ∈ M.commutant) :
        BoundedWeakNormal M (commutantReducingHom E M hE) := by
    …

    Mentions: OAI.KadisonKastler.BoundedWeakNormal, OAI.KadisonKastler.commutantReducingHom