OAI/GroupTheory/Thompson/StandardCharacterization.lean

GitHub source file

5 declarations, 0 contain sorry, 0 declared as axioms

Identification with the standard finite-breakpoint PL definition

The standard condition below states only a finite strictly ordered list of dyadic knots, the two endpoints, and the powers-of-two affine formulas. Coverage is derived from the endpoints; it is not an additional premise.

  1. def OAI.ThompsonNonamenability.StandardPLCondition line 17

    Source documentation

    The usual increasing PL interval homeomorphisms with finitely many dyadic breakpoints and slopes in the integer powers of two.

    def StandardPLCondition (f : UnitInterval ≃ₜ UnitInterval) : Prop :=
    …

    Mentions: OAI.ThompsonNonamenability.UnitInterval

  2. theorem OAI.ThompsonNonamenability.intervalHomeomorph_standardPL_iff line 30
  3. theorem OAI.ThompsonNonamenability.F.standardPLCondition line 52
  4. def OAI.ThompsonNonamenability.F.standardPLEquiv line 57

    Source documentation

    A faithful identification with the standard PL group carrier, with no uniform-grid or transport assumption in the right-hand side.

    def standardPLEquiv : F ≃ {f : UnitInterval ≃ₜ UnitInterval // StandardPLCondition f} where
    …

    Mentions: OAI.ThompsonNonamenability.F, OAI.ThompsonNonamenability.UnitInterval, OAI.ThompsonNonamenability.StandardPLCondition

  5. theorem OAI.ThompsonNonamenability.F.standardPLEquiv_apply line 68