OAI/Analysis/BoundedHochschild/ProperlyInfiniteIsometries.lean

GitHub source file

3 declarations, 0 contain sorry, 0 declared as axioms

Two isometries in an algebra without finite central summands

Comparison embeds the finite complement of a maximal properly infinite projection into that projection. Its two orthogonal copies then absorb the complement and give isometries with initial projection one.

  1. lemma OAI.BoundedHochschild.KadisonRingrose.finite_complement_embeds_properlyInfinite line 25
  2. theorem OAI.BoundedHochschild.KadisonRingrose.properlyInfinite_one line 53

    Source documentation

    The unit is properly infinite when no nonzero central corner is finite.

    theorem properlyInfinite_one (e : StrongDual ℂ X ≃ₗᵢ⋆[ℂ] M)
        (hno : NoFiniteCentralSummand M) : ProperlyInfiniteProjection (1 : M) := by
    …

    Mentions: OAI.BoundedHochschild.KadisonRingrose.NoFiniteCentralSummand, OAI.BoundedHochschild.KadisonRingrose.ProperlyInfiniteProjection

  3. theorem OAI.BoundedHochschild.KadisonRingrose.exists_two_orthogonal_isometries line 82

    Source documentation

    Actual orthogonal isometries, with no trace, separability, or factor assumption.

    theorem exists_two_orthogonal_isometries (e : StrongDual ℂ X ≃ₗᵢ⋆[ℂ] M)
        (hno : NoFiniteCentralSummand M) :
        ∃ v w : M, star v * v = 1 ∧ star w * w = 1 ∧ star v * w = 0 := by
    …

    Mentions: OAI.BoundedHochschild.KadisonRingrose.NoFiniteCentralSummand