import Mathlib import OAI.GroupTheory.SimpleAmenable.CentralCovers.AlignedPolygonGeneration namespace OAI section section open scoped symmDiff namespace SimpleAmenable open scoped commutatorElement open scoped commutatorElement section AlignedFiniteTables variable {α G : Type*} [Group G] (f : α → G) theorem finite_table_lift_in_subgroup_eventually (L : ℕ) (K : Subgroup (BoundedRelationCover L f)) {T : Type*} [Group T] [Finite T] (φ : T →* G) (hφ : ∀ s, φ s ∈ K.map (coverMap L f)) : ∃ B : ℕ, ∃ hLB : L ≤ B, ∀ M : ℕ, ∀ hBM : B ≤ M, ∃ ρ : T →* BoundedRelationCover M f, (coverMap M f).comp ρ = φ ∧ ρ.range ≤ K.map (coverTransition f (le_trans hLB hBM)) := by choose y hy hyq using hφ choose w hw using fun s => PresentedGroup.mk_surjective (shortRelations L f) (y s) have hwp : ∀ s, FreeGroup.lift f (w s) = φ s := by intro s rw [← coverMap_mk L f,hw s,hyq s] obtain ⟨B,hB⟩ := finite_table_lift_eventually f φ w hwp refine ⟨max L B,le_max_left _ _,fun M hM => ?_⟩ obtain ⟨ρ,hρ,hρw⟩ := hB M (le_trans (le_max_right _ _) hM) refine ⟨ρ,hρ,?_⟩ rintro z ⟨s,rfl⟩ refine ⟨y s,hy s,?_⟩ rw [← hw s,coverTransition_mk,hρw s] end AlignedFiniteTables section SourceAlignedTableCompatibility variable (a : ℕ) (r : CutRing) (m : ℕ) (hm : 2 ≤ m) theorem sourceAlignedGroup_map_full (M : ℕ) (t : Multiplicative (FreeAbelianGroup (Fin m × Fin 2)) →* BoundedRelationCover M (alternatingGenerator a r m hm)) (ht : (coverMap M (alternatingGenerator a r m hm)).comp t = sourceLatticeMap a r m hm) (I : Finset (Fin (m+1))) : (sourceAlignedGroup a r m hm M t I).map ((polygonAlternatingGroup a (m+1)).subtype.comp (coverMap M (alternatingGenerator a r m hm))) = polygonAlignedGroup a r m hm I := by rw [sourceAlignedGroup,alignedGroup_map] have htrans : ((polygonAlternatingGroup a (m+1)).subtype.comp (coverMap M (alternatingGenerator a r m hm))).comp t = sourceLatticeFullMap a r m hm := by rw [MonoidHom.comp_assoc,ht] rfl rw [htrans] rfl theorem sourceAlignedGroup_transition {L M : ℕ} (hLM : L ≤ M) (t : Multiplicative (FreeAbelianGroup (Fin m × Fin 2)) →* BoundedRelationCover L (alternatingGenerator a r m hm)) (I : Finset (Fin (m+1))) : (sourceAlignedGroup a r m hm L t I).map (coverTransition (alternatingGenerator a r m hm) hLM) = sourceAlignedGroup a r m hm M ((coverTransition (alternatingGenerator a r m hm) hLM).comp t) I := by rw [sourceAlignedGroup,alignedGroup_map] rfl theorem fiveTrack_conditional_preimage_aligned (hr : 0 < ordinary r ∧ ordinary r < 1/2) (M : ℕ) (t : Multiplicative (FreeAbelianGroup (Fin m × Fin 2)) →* BoundedRelationCover M (alternatingGenerator a r m hm)) (ht : (coverMap M (alternatingGenerator a r m hm)).comp t = sourceLatticeMap a r m hm) (ι : Fin 5 ↪ Fin (m+1)) (b : Fin (m+1)) (hb : b ∉ Set.range ι) (U : polygonAlgebra a) (g : alternatingGroup (Fin 5)) : ∃ y ∈ sourceAlignedGroup a r m hm M t (Finset.univ.map ι), ((coverMap M (alternatingGenerator a r m hm) y).val : polygonFullGroup a (m+1)) = conditionalHom U (fiveTrackHom ι g) := by have hh := fiveTrack_polygon_aligned a r m hm hr ι b hb U g rw [← sourceAlignedGroup_map_full a r m hm M t ht] at hh exact hh end SourceAlignedTableCompatibility end SimpleAmenable end end end OAI