OAI/GroupTheory/Thompson/PartitionColorFamily.lean

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10 declarations, 0 contain sorry, 0 declared as axioms

The actual finite family of colors, including zero outside admissibility

A basic partition is admissible when it respects every chosen parent and child. Its family color is always defined and lies in the unit ball. The option extension also assigns zero to a non-basic image; the group-level construction will supply the actual partial image partition.

  1. def OAI.ThompsonNonamenability.PartitionAdmissible line 25

    Source documentation

    One simultaneous condition for all actual parent and child intervals.

    def PartitionAdmissible (D : ℕ) (T : BasicPartition) : Prop :=
    …

    Mentions: OAI.ThompsonNonamenability.BasicPartition

  2. def OAI.ThompsonNonamenability.partitionFamilyColor line 29

    Source documentation

    The family color is zero whenever the actual partition is inadmissible.

    def partitionFamilyColor (hD : 0 < D) (f : UnitBall E → UnitBall E)
        (T : BasicPartition) (q : IntervalIndex D) : UnitBall E := by
    …

    Mentions: OAI.ThompsonNonamenability.UnitBall, OAI.ThompsonNonamenability.BasicPartition, OAI.ThompsonNonamenability.IntervalIndex

  3. theorem OAI.ThompsonNonamenability.partitionFamilyColor_of_admissible line 37
  4. theorem OAI.ThompsonNonamenability.partitionFamilyColor_of_not_admissible line 45
  5. theorem OAI.ThompsonNonamenability.partitionFamilyColor_norm_le line 51
  6. theorem OAI.ThompsonNonamenability.partitionFamilyColor_parent line 57

    Source documentation

    A parent's color is the map applied to its actual child-color mean.

    theorem partitionFamilyColor_parent (hD : 0 < D)
        (f : UnitBall E → UnitBall E) (T : BasicPartition)
        (h : PartitionAdmissible D T) (i : Fin D) :
        partitionFamilyColor hD f T (.inl i) =
          f (ballMean hD (fun j => partitionFamilyColor hD f T (.inr (i, j)))) := by
    …

    Mentions: OAI.ThompsonNonamenability.UnitBall, OAI.ThompsonNonamenability.BasicPartition, OAI.ThompsonNonamenability.PartitionAdmissible, OAI.ThompsonNonamenability.partitionFamilyColor, OAI.ThompsonNonamenability.ballMean

  7. def OAI.ThompsonNonamenability.optionFamilyColor line 67

    Source documentation

    Total zero extension at a non-basic image as well as an inadmissible one.

    def optionFamilyColor (hD : 0 < D) (f : UnitBall E → UnitBall E) :
        Option BasicPartition → IntervalIndex D → UnitBall E
      | none, _ => unitBallZero E
      | some T, q => partitionFamilyColor hD f T q

    Mentions: OAI.ThompsonNonamenability.UnitBall, OAI.ThompsonNonamenability.BasicPartition, OAI.ThompsonNonamenability.IntervalIndex, OAI.ThompsonNonamenability.unitBallZero, OAI.ThompsonNonamenability.partitionFamilyColor

  8. theorem OAI.ThompsonNonamenability.optionFamilyColor_none line 72
  9. theorem OAI.ThompsonNonamenability.optionFamilyColor_some line 76
  10. theorem OAI.ThompsonNonamenability.optionFamilyColor_norm_le line 80