OAI/Geometry/HyperbolicGroups/SetoidGlue.lean

GitHub source file

9 declarations, 0 contain sorry, 0 declared as axioms

  1. def OAI.HyperbolicObstruction.PictureSwitch.glue line 14

    Source documentation

    Identifying two classes, without making any other identifications.

    def glue {D : Type*} (s : Setoid D) (a b : D) : Setoid D := by
    …
  2. lemma OAI.HyperbolicObstruction.PictureSwitch.glue_iff line 21
  3. lemma OAI.HyperbolicObstruction.PictureSwitch.le_glue line 29
  4. lemma OAI.HyperbolicObstruction.PictureSwitch.glue_pair line 37
  5. lemma OAI.HyperbolicObstruction.PictureSwitch.glue_le line 42
  6. lemma OAI.HyperbolicObstruction.PictureSwitch.glue_eq_of_rel line 52
  7. lemma OAI.HyperbolicObstruction.PictureSwitch.glue_monotone line 55
  8. theorem OAI.HyperbolicObstruction.PictureSwitch.card_glue_of_not_rel line 62

    Source documentation

    Exactly one component is lost when previously distinct classes are glued.

    theorem card_glue_of_not_rel (h : ¬ s a b) :
        Nat.card (Quotient (glue s a b)) + 1 = Nat.card (Quotient s) := by
    …

    Mentions: OAI.HyperbolicObstruction.PictureSwitch.glue

  9. theorem OAI.HyperbolicObstruction.PictureSwitch.card_glue line 91

    Source documentation

    A uniformly phrased count, including the already-related case.

    theorem card_glue : (Nat.card (Quotient (glue s a b)) : ℤ) =
        Nat.card (Quotient s) - if s a b then 0 else 1 := by
    …

    Mentions: OAI.HyperbolicObstruction.PictureSwitch.glue