fpvandoorn/carleson
Source indexedlemma ยท leanprover/lean4:v4.32.0
norm_Ks_le'
Carleson.Antichain.Basic ยท Carleson/Antichain/Basic.lean:126 to 150
Mathematical statement
Exact Lean statement
lemma norm_Ks_le' {x y : X} {๐ : Set (๐ X)} (p : ๐) (hxE : x โ E โp) (hy : Ks (๐ฐ p.1) x y โ 0) :
โKs (๐ฐ p.1) x yโโ โค 2 ^ (6 * a + (๐ + 1) * a ^ 3) / volume (ball (๐ p.1) (8 * D ^ ๐ฐ p.1))Complete declaration
Lean source
Full Lean sourceLean 4
lemma norm_Ks_le' {x y : X} {๐ : Set (๐ X)} (p : ๐) (hxE : x โ E โp) (hy : Ks (๐ฐ p.1) x y โ 0) : โKs (๐ฐ p.1) x yโโ โค 2 ^ (6 * a + (๐ + 1) * a ^ 3) / volume (ball (๐ p.1) (8 * D ^ ๐ฐ p.1)) := by have hDpow_pos : 0 < (D : โ) ^ ๐ฐ p.1 := defaultD_pow_pos .. have h8Dpow_pos : 0 < 8 * (D : โ) ^ ๐ฐ p.1 := mul_defaultD_pow_pos _ (by linarith) _ have hdist_cp : dist x (๐ p) โค 4 * D ^ ๐ฐ p.1 := (mem_ball.mp (Grid_subset_ball hxE.1)).le have h : โKs (๐ฐ p.1) x yโโ โค 2 ^ a ^ 3 / volume (ball x (D ^ (๐ฐ p.1 - 1) / 4)) := by apply kernel_bound.trans grw [C_K, โ Nat.cast_pow, NNReal.rpow_natCast, ENNReal.coe_pow, coe_ofNat, vol, (dist_mem_Icc_of_Ks_ne_zero hy).1] apply h.trans rw [zpow_subโ (by simp), zpow_one, div_div] apply (ineq_6_1_7 x p).trans have ha : 6 * a + (๐ + 1) * a ^ 3 = (5 * a + (๐ + 1) * a ^ 3) + a := by lia simp only [div_eq_mul_inv, ge_iff_le] rw [ha, pow_add _ (5 * a + (๐ + 1) * a ^ 3) a, mul_assoc] gcongr suffices volume (ball (๐ p.1) (8 * D ^ ๐ฐ p.1)) โค 2 ^ a * volume (ball x (8 * D ^ ๐ฐ p.1)) by grw [โ inv_inv (2 ^ a), โ ENNReal.mul_inv (.inl (by simp)) (.inl (by finiteness)), ENNReal.inv_le_inv, โ ENNReal.div_eq_inv_mul, ENNReal.div_le_of_le_mul' this] have h2 : dist x (๐ p) + 8 * D ^ ๐ฐ p.1 โค 2 * (8 * D ^ ๐ฐ p.1) := calc _ โค (4 : โ) * D ^ ๐ฐ p.1 + 8 * D ^ ๐ฐ p.1 := (add_le_add_iff_right _).mpr hdist_cp _ โค _ := by linarith convert measure_ball_le_of_dist_le' (ฮผ := volume) zero_lt_two h2 simp [As]