import Mathlib import OAI.Geometry.Cannon.Boundary.BoundaryModulusBounded import OAI.Geometry.Cannon.Energy.ApproxSelfSimilar namespace OAI section section section noncomputable section namespace CannonRelease open CannonGraph CannonVisual CannonGeometry CannonNet CannonCells CannonCharts Set Metric universe v variable {G : Type v} [Group G] [TopologicalSpace G] [DiscreteTopology G] variable (D : CayleyData G) {δ : ℕ} (hδ : Thin D.graph δ) theorem boundary_uniformization_inputs (φ : Boundary D ≃ₜ SphereTwo) : let _ := visualMetricSpace D hδ let a := Real.exp (2*visualExponent δ) let LE := 8*Real.exp (visualExponent δ*(4*(8*δ+6):ℕ)) ∀ d κ : ℝ, 0 < d → d < diam (univ : Set (Boundary D))/10 → d ≤ 1/(LE*3^2) → 2*a < κ → PathConnectedSpace (Boundary D) ∧ ApproxSelfSimilar (Boundary D) ∧ ∃ T : ℕ → Finset (Boundary D), ∃ N : ℕ → ℕ, ∃ B : ℝ, ∀ m, IsApproximation (fun i : T (N m) => i.val) (fun i : T (N m) => ball i.val (2*(a^(N m))⁻¹)) ((2:ℝ)^m)⁻¹ κ ∧ modulus (fun i : T (N m) => ball i.val (2*(a^(N m))⁻¹)) (macroFamily d) ≤ B := by classical let _ := visualMetricSpace D hδ dsimp only intro d κ hd hdia hdc hκ let a := Real.exp (2*visualExponent δ) have ha : 1 < a := Real.one_lt_exp_iff.mpr (mul_pos (by norm_num) (visualExponent_pos δ)) let _ : PathConnectedSpace SphereTwo := CannonCharts.sphere_pathConnected refine ⟨φ.symm.surjective.pathConnectedSpace φ.symm.continuous, boundary_approx_self_similar D hδ,?_⟩ obtain ⟨T,hT⟩ := exists_net_sequence (X:=Boundary D) ha have hscale (m : ℕ) : ∃ n : ℕ, ((2:ℝ)^m)⁻¹/a < (a^n)⁻¹ ∧ (a^n)⁻¹ ≤ ((2:ℝ)^m)⁻¹ := by apply exists_scale_below ha (by positivity) exact inv_le_one_of_one_le₀ (one_le_pow₀ (by norm_num)) choose N hNlow hNupp using hscale have hsep (n : ℕ) (i j : T n) (hij : i ≠ j) : (a^n)⁻¹ ≤ dist i.val j.val := (hT n).1 i.val i.property j.val j.property (fun hh => hij (Subtype.ext hh)) have hnet (n : ℕ) (x : Boundary D) : ∃ i : T n, dist i.val x ≤ (a^n)⁻¹ := by obtain ⟨y,hy,hh⟩ := (hT n).2 x exact ⟨⟨y,hy⟩,hh⟩ have hdia' : d < diam (univ : Set (Boundary D)) := by have := diam_nonneg (s:= (univ : Set (Boundary D))) linarith obtain ⟨B,hB⟩ := boundary_modulus_bounded D hδ φ d hd hdia' hdc (fun n => ↥(T n)) (fun n i => i.val) hsep hnet refine ⟨T,N,B,?_⟩ intro m exact ⟨balls_isApproximation (fun i : T (N m) => i.val) ha (by positivity) hκ (hNlow m) (hNupp m) (hsep (N m)) (hnet (N m)),hB (N m)⟩ end CannonRelease end end end end end OAI