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Add lean source and binary files (part 95)
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import Mathlib
import OAI.MeasureTheory.FalconerCompletion.Measures.AmbientGridCell3
namespace OAI
/-! Recursive policies and quantitative depth estimates. -/
section
section
open Set MeasureTheory
open scoped ComplexConjugate RealInnerProductSpace
namespace GraphLiteralSupport
namespace Attempt4FullFar
open Set Metric
lemma exists_far_separation_powerND (d : ℕ) :
∃ k : ℕ, 1000*(d+1:ℝ)<(2:ℝ)^k ∧ (2:ℝ)^k<4000*(d+1:ℝ) := by
obtain ⟨n,hn,hn'⟩ := exists_nat_pow_near (x := 1000*(d+1:ℝ)) (y := (2:ℝ))
(by have hd : (0:ℝ)≤d := Nat.cast_nonneg d; linarith) (by norm_num)
refine ⟨n+1,hn',?_⟩
rw [pow_succ]
nlinarith
def farSeparatedGridND {d : ℕ} (b : ℕ) (K : ℝ) (X Y : Fin d → ℤ) : Prop :=
K/(8*(2:ℝ)^b)≤dist (ambientGridCenter b X) (ambientGridCenter b Y) ∧
dist (ambientGridCenter b X) (ambientGridCenter b Y)≤4*K/(2:ℝ)^b
theorem farSeparatedGridND_of_lengths {d b : ℕ} {K : ℝ}
(hK : 16*(d+1:ℝ)≤K) {X Y : Fin d → ℤ} {x y : EuclideanSpace ℝ (Fin d)}
(hx : x∈ambientGridCell b X) (hy : y∈ambientGridCell b Y)
(hlo : K/(4*(2:ℝ)^b)≤dist x y) (hhi : dist x y≤K/(2:ℝ)^b) :
farSeparatedGridND b K X Y := by
have htp : 0<(2:ℝ)^b := by positivity
have hcx := ambientGridCell_dist_le hx (ambientGridCenter_mem b X)
have hcy := ambientGridCell_dist_le hy (ambientGridCenter_mem b Y)
have hxy := dist_triangle4 x (ambientGridCenter b X) (ambientGridCenter b Y) y
have hcc := dist_triangle4 (ambientGridCenter b X) x y (ambientGridCenter b Y)
rw [dist_comm x (ambientGridCenter b X)] at hxy
rw [dist_comm y (ambientGridCenter b Y)] at hcc
have hscale := div_le_div_of_nonneg_right hK htp.le
have hscale' : 16*((d+1:ℝ)/(2:ℝ)^b)≤K/(2:ℝ)^b := by simpa only [mul_div_assoc] using hscale
have he₁ : K/(4*(2:ℝ)^b)=(K/(2:ℝ)^b)/4 := by ring
have he₂ : K/(8*(2:ℝ)^b)=(K/(2:ℝ)^b)/8 := by ring
have he₃ : 4*K/(2:ℝ)^b=4*(K/(2:ℝ)^b) := by ring
dsimp [farSeparatedGridND]
rw [he₂,he₃]
rw [he₁] at hlo
constructor <;> linarith
theorem farSeparatedGridND_partner_card {d : ℕ} (b : ℕ) {K : ℝ} (hK : 0≤K)
(X : Fin d → ℤ) (P : Finset (Fin d → ℤ))
(hP : ∀ Y∈P, farSeparatedGridND b K X Y) :
(P.card:ℝ)≤(8*K+5)^d := by
have hh := ambientGridCenter_ball_card b P (ambientGridCenter b X)
(r := 4*K/(2:ℝ)^b) (by positivity) (fun Y hY => by
rw [dist_comm]; exact (hP Y hY).2)
convert hh using 1
congr 1
field_simp; ring
theorem exists_far_common_depthND {D₁ D₂ K : ℝ} (hD₁ : 0<D₁) (hD₂ : 0<D₂)
(hcomp : max D₁ D₂≤2*min D₁ D₂) (hsize : max D₁ D₂≤K) :
∃ b : ℕ, K/(4*(2:ℝ)^b)≤D₁ ∧ D₁≤K/(2:ℝ)^b ∧
K/(4*(2:ℝ)^b)≤D₂ ∧ D₂≤K/(2:ℝ)^b ∧
K/(2*(2:ℝ)^b)< max D₁ D₂ := by
have hD : 0< max D₁ D₂ := (lt_min hD₁ hD₂).trans_le min_le_max
have hK : 0<K := hD.trans_le hsize
obtain ⟨b,hb,hb'⟩ := exists_nat_pow_near
((one_le_div hD).mpr hsize) (by norm_num : (1:ℝ)<2)
have hp : 0<(2:ℝ)^b := by positivity
have hu : max D₁ D₂≤K/(2:ℝ)^b := by
apply (le_div_iff₀ hp).mpr
have hh := (le_div_iff₀ hD).mp hb
nlinarith
have hl : K/(2*(2:ℝ)^b)< max D₁ D₂ := by
apply (div_lt_iff₀ (by positivity : 0<2*(2:ℝ)^b)).mpr
rw [pow_succ] at hb'
have hh := (div_lt_iff₀ hD).mp hb'
nlinarith
have hm : K/(4*(2:ℝ)^b)≤ min D₁ D₂ := by
have he : K/(2*(2:ℝ)^b)=2*(K/(4*(2:ℝ)^b)) := by ring
rw [he] at hl
linarith
exact ⟨b,hm.trans (min_le_left _ _),(le_max_left _ _).trans hu,
hm.trans (min_le_right _ _),(le_max_right _ _).trans hu,hl⟩
lemma far_common_depth_strictND {d a b : ℕ} {D K : ℝ}
(hK : 16*(d+1:ℝ)≤K) (hl : K/(2*(2:ℝ)^b)<D)
(hu : D≤(d+1:ℝ)/(2:ℝ)^a) : a<b := by
by_contra h
have hba : b≤a := by omega
have hpow : (2:ℝ)^b≤(2:ℝ)^a := pow_le_pow_right₀ (by norm_num) hba
have hKp : 0<K := by have hd : (0:ℝ)≤d := Nat.cast_nonneg d; linarith
have hscale : K/(2*(2:ℝ)^a)≤K/(2*(2:ℝ)^b) :=
div_le_div_of_nonneg_left hKp.le (by positivity) (by gcongr)
have hbad : K/(2*(2:ℝ)^a)<(d+1:ℝ)/(2:ℝ)^a := hscale.trans_lt (hl.trans_le hu)
have he : K/(2*(2:ℝ)^a)=(K/2)/(2:ℝ)^a := by ring
rw [he] at hbad
have hh := (div_lt_div_iff_of_pos_right (by positivity : 0<(2:ℝ)^a)).mp hbad
linarith
end Attempt4FullFar
end GraphLiteralSupport
end
end
end OAI