OAI/Analysis/KadisonKastler/RightBoundedVector.lean

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7 declarations, 0 contain sorry, 0 declared as axioms

Constructing a commutant operator from a bounded right vector

A bound on the map a Ω ↦ a ξ gives its continuous extension. Density makes the extension commute with the represented algebra and unique. This is the bounded-vector bridge for the modular commutant argument.

  1. def OAI.KadisonKastler.rightVectorOperator line 21

    Source documentation

    Extension of right multiplication, whenever its algebra-vector bound holds.

    def rightVectorOperator : H →L[ℂ] H :=
    …
  2. theorem OAI.KadisonKastler.rightVectorOperator_apply line 29
  3. theorem OAI.KadisonKastler.rightVectorOperator_norm_le line 34
  4. theorem OAI.KadisonKastler.rightVectorOperator_vector line 38
  5. theorem OAI.KadisonKastler.rightVectorOperator_mem_commutant line 43
  6. theorem OAI.KadisonKastler.commutant_operator_eq_of_vector line 59

    Source documentation

    A commutant operator is determined by its value at a cyclic vector.

    theorem commutant_operator_eq_of_vector {S T : H →L[ℂ] H}
        (hS : S ∈ M.commutant) (hT : T ∈ M.commutant) (he : S Ω = T Ω) : S = T := by
    …
  7. theorem OAI.KadisonKastler.exists_commutant_operator_iff_vector_bound line 76

    Source documentation

    The right-vector estimate is equivalent to an actual bounded operator in the commutant.

    theorem exists_commutant_operator_iff_vector_bound :
        (∃ T : H →L[ℂ] H, T ∈ M.commutant ∧ ‖T‖ ≤ C ∧ T Ω = ξ) ↔
          ∀ a : Algebra M, ‖a.val ξ‖ ≤ C * ‖a.val Ω‖ := by
    …

    Mentions: OAI.KadisonKastler.Algebra