OAI/Analysis/FiniteFactor/CrossedProduct/Rotation.lean

GitHub source file

7 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.FiniteFactor.sourceCircleRepresentative line 11
  2. theorem OAI.FiniteFactor.sourceCircleRepresentative_measurable line 14
  3. theorem OAI.FiniteFactor.sourceCircleRepresentative_coe line 17
  4. theorem OAI.FiniteFactor.sourceCircle_mk_preserving line 25
  5. theorem OAI.FiniteFactor.sourceCircleRepresentative_preserving line 30
  6. theorem OAI.FiniteFactor.unitInterval_rotate_preserving line 42

    Source documentation

    Translation modulo one preserves the exact real representative measure.

    theorem unitInterval_rotate_preserving (a : ℝ) :
        MeasurePreserving (fun x : ℝ => Int.fract (x+a)) unitIntervalMeasure unitIntervalMeasure := by
    …

    Mentions: OAI.FiniteFactor.unitIntervalMeasure

  7. theorem OAI.FiniteFactor.coordinateRotate_preserving line 53

    Source documentation

    All integer iterates of the countable source rotation preserve its actual infinite product measure. This is not an assumed action property.

    theorem coordinateRotate_preserving {ι : Type*} (θ : ι → ℝ) (k : ℤ) :
        MeasurePreserving (coordinateRotate θ k)
          (Measure.infinitePi (fun _ : ι => unitIntervalMeasure))
          (Measure.infinitePi (fun _ : ι => unitIntervalMeasure)) := by
    …

    Mentions: OAI.FiniteFactor.coordinateRotate, OAI.FiniteFactor.unitIntervalMeasure