OAI/Geometry/HyperbolicGroups/SetoidGlue.lean
9 declarations, 0 contain sorry, 0 declared as axioms
- def
OAI.HyperbolicObstruction.PictureSwitch.glueline 14Source documentation
Identifying two classes, without making any other identifications.
def glue {D : Type*} (s : Setoid D) (a b : D) : Setoid D := by … - lemma
OAI.HyperbolicObstruction.PictureSwitch.glue_iffline 21 - lemma
OAI.HyperbolicObstruction.PictureSwitch.le_glueline 29 - lemma
OAI.HyperbolicObstruction.PictureSwitch.glue_pairline 37 - lemma
OAI.HyperbolicObstruction.PictureSwitch.glue_leline 42 - lemma
OAI.HyperbolicObstruction.PictureSwitch.glue_eq_of_relline 52 - lemma
OAI.HyperbolicObstruction.PictureSwitch.glue_monotoneline 55 - theorem
OAI.HyperbolicObstruction.PictureSwitch.card_glue_of_not_relline 62Source 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 … - theorem
OAI.HyperbolicObstruction.PictureSwitch.card_glueline 91Source 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 …