OAI/Geometry/HyperbolicGroups/IntegralCellularBoundary.lean

GitHub source file

12 declarations, 0 contain sorry, 0 declared as axioms

Integral chains for a polygon incidence system, with all lifted edges independent. This is the algebraic cellular boundary needed for the source's cycle producer. It does not identify these chains with a topological homology theory.

  1. def OAI.HyperbolicObstruction.IntegralIncidence.reverse line 20

    Source documentation

    Formal dart reversal. Loop edges and parallel indexed edges remain distinct.

    def reverse (e : E × Bool) : E × Bool := (e.1, !e.2)
  2. theorem OAI.HyperbolicObstruction.IntegralIncidence.reverse_reverse line 22
  3. def OAI.HyperbolicObstruction.IntegralIncidence.liftedStart line 27
  4. def OAI.HyperbolicObstruction.IntegralIncidence.liftedReverse line 28
  5. theorem OAI.HyperbolicObstruction.IntegralIncidence.liftedReverse_reverse line 34
  6. def OAI.HyperbolicObstruction.IntegralIncidence.edgeChain line 42

    Source documentation

    Signed contribution of a lifted dart to the free integral edge module. A negative dart is indexed at the start of its positive reverse.

    def edgeChain (e : G × (E × Bool)) : (G × E) →₀ ℤ :=
    …
  7. theorem OAI.HyperbolicObstruction.IntegralIncidence.edgeChain_reverse line 47
  8. def OAI.HyperbolicObstruction.IntegralIncidence.edgeBoundary line 54

    Source documentation

    The boundary of a positive lifted edge.

    def edgeBoundary (e : G × E) : (G × V) →₀ ℤ :=
    …
  9. def OAI.HyperbolicObstruction.IntegralIncidence.d₁ line 58
  10. lemma OAI.HyperbolicObstruction.IntegralIncidence.boundary_edgeChain line 62
  11. structure OAI.HyperbolicObstruction.IntegralIncidence.Polygons line 72

    Source documentation

    An indexed polygonal attaching system, before topological realization.

    structure Polygons (E V C : Type*) where
    …
  12. lemma OAI.HyperbolicObstruction.IntegralIncidence.group_prefix_rotate line 79