OAI/GroupTheory/Thompson/RecursiveColoring.lean

GitHub source file

5 declarations, 0 contain sorry, 0 declared as axioms

Recursive unit-ball colors of actual basic dyadic partitions

The recursion uses the number of actual cells. Restriction to any selected internal interval strictly decreases that number. The mean is bundled with its genuine unit-ball proof before it is supplied to the map.

  1. def OAI.ThompsonNonamenability.partitionColor line 23
  2. theorem OAI.ThompsonNonamenability.partitionColor_of_respects line 36

    Source documentation

    The recursive branch, with its actual restricted partitions.

    theorem partitionColor_of_respects (I : Fin D → BasicInterval)
        (hI : ∀ i, (I i).Internal) (hD : 0 < D)
        (f : UnitBall E → UnitBall E) (T : BasicPartition)
        (h : ∀ i, T.Respects (I i)) :
        partitionColor I hI hD f T = f (ballMean hD (fun i =>
          partitionColor I hI hD f (T.restrict (I i) (h i)))) := by
    …

    Mentions: OAI.ThompsonNonamenability.BasicInterval, OAI.ThompsonNonamenability.UnitBall, OAI.ThompsonNonamenability.BasicPartition, OAI.ThompsonNonamenability.partitionColor, OAI.ThompsonNonamenability.ballMean

  3. theorem OAI.ThompsonNonamenability.partitionColor_of_not_respects line 46

    Source documentation

    Partitions failing the simultaneous respect condition receive zero.

    theorem partitionColor_of_not_respects (I : Fin D → BasicInterval)
        (hI : ∀ i, (I i).Internal) (hD : 0 < D)
        (f : UnitBall E → UnitBall E) (T : BasicPartition)
        (h : ¬∀ i, T.Respects (I i)) :
        partitionColor I hI hD f T = unitBallZero E := by
    …

    Mentions: OAI.ThompsonNonamenability.BasicInterval, OAI.ThompsonNonamenability.UnitBall, OAI.ThompsonNonamenability.BasicPartition, OAI.ThompsonNonamenability.partitionColor, OAI.ThompsonNonamenability.unitBallZero

  4. theorem OAI.ThompsonNonamenability.partitionColor_norm_le line 54
  5. theorem OAI.ThompsonNonamenability.partitionColor_restrict line 62

    Source documentation

    Applying the recursion to a parent restriction gives the actual child mean. The normalized two-step restriction is replaced by the proved composite one.

    theorem partitionColor_restrict (I : Fin D → BasicInterval)
        (hI : ∀ i, (I i).Internal) (hD : 0 < D)
        (f : UnitBall E → UnitBall E) (T : BasicPartition) (i : Fin D)
        (hparent : T.Respects (I i))
        (hchild : ∀ j, T.Respects ((I i).comp (I j))) :
        partitionColor I hI hD f (T.restrict (I i) hparent) =
          f (ballMean hD (fun j => partitionColor I hI hD f
            (T.restrict ((I i).comp (I j)) (hchild j)))) := by
    …

    Mentions: OAI.ThompsonNonamenability.BasicInterval, OAI.ThompsonNonamenability.UnitBall, OAI.ThompsonNonamenability.BasicPartition, OAI.ThompsonNonamenability.partitionColor, OAI.ThompsonNonamenability.ballMean