OAI/Geometry/HyperbolicGroups/SimpleLetterPresentation.lean

GitHub source file

8 declarations, 0 contain sorry, 0 declared as axioms

  1. inductive OAI.HyperbolicObstruction.LetterPresentation.SimpleWordRelator line 16

    Source documentation

    Exactly the source03 finite presentation: all simple cycles of each included fan and compatible included top graph, plus the two decorations. The underlying template graph is not quotiented by its random labels.

    inductive SimpleWordRelator : List (Alphabet n) → Prop
      | fan (l : Field → Alphabet n) (i : Fin 7)
          (present : w (TableModel.row rowSupport l (.inl i)) = true)
          (v : CoreGeometry.Vertex) (p : (CoreWordGraph.graph (fan i)).Walk v v)
          (simple : p.IsCycle) :
          SimpleWordRelator (GraphWordFilling.word (CoreWordGraph.label (fan i) n l) p)
      | top (l : Field → Alphabet n)
          (present : w (TableModel.row rowSupport l (.inr (.inl ()))) = true)
          (fans : ∀ i : Fin 7, w (TableModel.row rowSupport l (.inl i)) = true)
          (v : CoreGeometry.Vertex) (p : (CoreWordGraph.graph Finset.univ).Walk v v)
          (simple : p.IsCycle) :
          SimpleWordRelator (GraphWordFilling.word (CoreWordGraph.label Finset.univ n l) p)
    …

    Mentions: OAI.HyperbolicObstruction.LetterPresentation.Alphabet, OAI.HyperbolicObstruction.TableModel.row, OAI.HyperbolicObstruction.CoreGeometry.Vertex, OAI.HyperbolicObstruction.CoreWordGraph.graph, OAI.HyperbolicObstruction.GraphWordFilling.word, OAI.HyperbolicObstruction.CoreWordGraph.label

  2. lemma OAI.HyperbolicObstruction.LetterPresentation.simpleWordRelator_length line 33
  3. theorem OAI.HyperbolicObstruction.LetterPresentation.simpleWordRelator_finite line 45

    Source documentation

    Finiteness is proved from literal words, including coinciding labels and repeated rows, not asserted as an extra presentation hypothesis.

    theorem simpleWordRelator_finite : Set.Finite {z | SimpleWordRelator n w d z} := by
    …

    Mentions: OAI.HyperbolicObstruction.LetterPresentation.SimpleWordRelator

  4. lemma OAI.HyperbolicObstruction.LetterPresentation.simpleWordRelator_original line 53
  5. lemma OAI.HyperbolicObstruction.LetterPresentation.fan_fields line 72
  6. lemma OAI.HyperbolicObstruction.LetterPresentation.top_fields line 81
  7. theorem OAI.HyperbolicObstruction.LetterPresentation.relator_simple_filling line 89

    Source documentation

    Every ORIGINAL relator has a quantitative derivation in the finite simple-cycle presentation. The bound is its literal length (zero included).

    theorem relator_simple_filling {z : List (Alphabet n)} (hz : WordRelator n w d z) :
        ∃ a ≤ z.length, WordPictures.Homotopy (SimpleWordRelator n w d) z [] a := by
    …

    Mentions: OAI.HyperbolicObstruction.LetterPresentation.Alphabet, OAI.HyperbolicObstruction.LetterPresentation.WordRelator, OAI.HyperbolicObstruction.WordPictures.Homotopy, OAI.HyperbolicObstruction.LetterPresentation.SimpleWordRelator

  8. theorem OAI.HyperbolicObstruction.LetterPresentation.simple_presentation_normalClosure line 121

    Source documentation

    Exact normal-closure equality, giving the same original marked group, not merely a surjection from a conveniently chosen finite presentation.

    theorem simple_presentation_normalClosure :
        Subgroup.normalClosure (FreeGroup.mk '' SimpleWordRelator n w d) =
        Subgroup.normalClosure (Relator n w d) := by
    …

    Mentions: OAI.HyperbolicObstruction.LetterPresentation.SimpleWordRelator, OAI.HyperbolicObstruction.LetterPresentation.Relator