OAI/Analysis/KadisonKastler/MeasurableNatEnumeration.lean

GitHub source file

14 declarations, 0 contain sorry, 0 declared as axioms

Measurably enumerating nonzero frame indices

The nth index of a point-dependent subset of the naturals is measurable when each membership predicate is measurable. The library's value zero outside the finite range is retained; dimension strata remove that case.

  1. def OAI.KadisonKastler.measurableIndexCount line 21
  2. theorem OAI.KadisonKastler.measurable_indexCount line 25
  3. theorem OAI.KadisonKastler.nth_eq_nonzero_iff line 36
  4. theorem OAI.KadisonKastler.measurable_natNth line 50
  5. def OAI.KadisonKastler.frameIndexAvailable line 77

    Source documentation

    There are at least k + 1 indices satisfying the predicate.

    def frameIndexAvailable (p : ℕ → Prop) (k : ℕ) : Prop :=
    …
  6. theorem OAI.KadisonKastler.frameIndexAvailable_mono line 80
  7. theorem OAI.KadisonKastler.measurableSet_frameIndexAvailable line 85
  8. theorem OAI.KadisonKastler.frameIndexAvailable_valid line 97
  9. theorem OAI.KadisonKastler.frameIndexAvailable_count line 106
  10. def OAI.KadisonKastler.frameIndexEquiv line 114

    Source documentation

    The ascending enumeration, restricted to its genuine indices, is a bijection.

    def frameIndexEquiv (p : ℕ → Prop) : {k // frameIndexAvailable p k} ≃ {m // p m} := by
    …

    Mentions: OAI.KadisonKastler.frameIndexAvailable

  11. def OAI.KadisonKastler.frameDimensionStratum line 123

    Source documentation

    Index zero is the infinite-rank stratum; index n + 1 is rank n.

    def frameDimensionStratum (p : X → ℕ → Prop) : ℕ → Set X
      | 0 => {x | ∀ k, frameIndexAvailable (p x) k}
      | n + 1 => {x | (∀ k < n, frameIndexAvailable (p x) k) ∧
          ¬frameIndexAvailable (p x) n}

    Mentions: OAI.KadisonKastler.frameIndexAvailable

  12. theorem OAI.KadisonKastler.measurableSet_frameDimensionStratum line 128
  13. theorem OAI.KadisonKastler.exists_frameDimensionStratum line 144
  14. theorem OAI.KadisonKastler.frameDimensionStratum_finite_iff line 154