OAI/GroupTheory/Kervaire/RelatorRigidity.lean
23 declarations, 0 contain sorry, 0 declared as axioms
- def
OAI.KervaireRibbon.cornerline 15Source documentation
The coefficient on the corner immediately following a dart.
def corner (σ θ : Perm D) (u : D → A) (d : D) : A := u (θ d) * (u (σ d))⁻¹ …
- lemma
OAI.KervaireRibbon.corner_gaugeline 18 - lemma
OAI.KervaireRibbon.align_distinct_facesline 29Source documentation
Independent face gauges can align two vertices precisely when the two relevant faces are distinct.
lemma align_distinct_faces (σ θ : Perm D) (hθ : ∀ d, θ (θ d) = d) (u : D → A) {p q : D} (hpq : ¬ (σ*θ).SameCycle p q) : ∃ v : D → A, corner σ θ v = corner σ θ u ∧ v q = v p := by …Mentions: OAI.KervaireRibbon.corner
- lemma
OAI.KervaireRibbon.planar_symmline 40 - lemma
OAI.KervaireRibbon.cap_vertexline 50 - lemma
OAI.KervaireRibbon.cap_vertex_otherline 74 - lemma
OAI.KervaireRibbon.planar_capline 87 - lemma
OAI.KervaireRibbon.suppress_uline 111 - lemma
OAI.KervaireRibbon.corner_capline 132 - lemma
OAI.KervaireRibbon.components_mapline 155 - lemma
OAI.KervaireRibbon.components_equivline 172 - lemma
OAI.KervaireRibbon.classes_components_equivline 182 - lemma
OAI.KervaireRibbon.planar_equivline 187 - lemma
OAI.KervaireRibbon.connected_equivline 195 - lemma
OAI.KervaireRibbon.sum_eq_zero_of_oppositeline 211 - lemma
OAI.KervaireRibbon.vertex_balanceline 216 - lemma
OAI.KervaireRibbon.balanced_verticesline 229Source documentation
Exact positive/negative disk coordinates, derived from the sign conservation of the bands rather than postulated as a balancing hypothesis.
lemma balanced_vertices (ε : V → ℤ) (hε : ∀ v, ε v = 1 ∨ ε v = -1) (hzero : (∑ v, ε v) = 0) : ∃ q : ({v // ε v = 1} ⊕ {v // ε v = 1}) ≃ V, (∀ k, ε (q (Sum.inl k)) = 1) ∧ (∀ k, ε (q (Sum.inr k)) = -1) := by … - def
OAI.KervaireRibbon.vertexNextline 262 - def
OAI.KervaireRibbon.vertexCornerline 264 - theorem
OAI.KervaireRibbon.relator_corner_rigidityline 267 - structure
OAI.KervaireRibbon.DiskAtlasline 348Source documentation
Disjoint relator disks in a larger ribbon diagram. The other darts may belong to an outside word or be isolated markers from previous cancellations.
structure DiskAtlas (ρ : Perm I) (a : I → A) (s : I → ℤ) (σ : Perm D) (t : D → ℤ) where … - lemma
OAI.KervaireRibbon.disk_sameCycleline 359Source documentation
Every dart on a word disk lies in the same ribbon component as its chosen representative.
lemma disk_sameCycle (ρ : Perm I) (hρ : ∀ i j, ρ.SameCycle i j) (a : I → A) (s : I → ℤ) (σ : Perm D) (t : D → ℤ) (b : DiskAtlas (V := V) ρ a s σ t) (v : V) (i j : I) : …Mentions: OAI.KervaireRibbon.DiskAtlas
- theorem
OAI.KervaireRibbon.atlas_component_rigidityline 388Source documentation
Restricting whole relator disks to one component retains the literal word coordinates, including the actual reversed corners of negative disks.
theorem atlas_component_rigidity [Nonempty I] (ρ : Perm I) (hρ : ∀ i j, ρ.SameCycle i j) (a : I → A) (s : I → ℤ) (hs : ∀ i, s i = 1 ∨ s i = -1) (hsum : (∑ i, s i) = 1 ∨ (∑ i, s i) = -1) (σ θ : Perm D) (hθ : ∀ d, θ (θ d) = d) (t : D → ℤ) (ht : ∀ d, t (θ d) = -t d) (hp : planar σ θ) (b : DiskAtlas (V := V) ρ a s σ t) (u : D → A) (p : D) …Mentions: OAI.KervaireRibbon.planar, OAI.KervaireRibbon.DiskAtlas