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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 โˆˆ E โ†‘p) (hy : Ks (๐”ฐ p.1) x y โ‰  0) :
    โ€–Ks (๐”ฐ p.1) x yโ€–โ‚‘ โ‰ค 2 ^ (6 * a + (๐•” + 1) * a ^ 3) / volume (ball (๐”  p.1) (8 * D ^ ๐”ฐ p.1))

Complete declaration

Lean source

Canonical source
Full Lean sourceLean 4
lemma norm_Ks_le' {x y : X} {๐”„ : Set (๐”“ X)} (p : ๐”„) (hxE : x โˆˆ E โ†‘p) (hy : Ks (๐”ฐ p.1) x y โ‰  0) :    โ€–Ks (๐”ฐ p.1) x yโ€–โ‚‘ โ‰ค 2 ^ (6 * a + (๐•” + 1) * a ^ 3) / volume (ball (๐”  p.1) (8 * D ^ ๐”ฐ p.1)) := by  have hDpow_pos : 0 < (D : โ„) ^ ๐”ฐ p.1 := defaultD_pow_pos ..  have h8Dpow_pos : 0 < 8 * (D : โ„) ^ ๐”ฐ p.1 := mul_defaultD_pow_pos _ (by linarith) _  have hdist_cp : dist x (๐”  p) โ‰ค 4 * D ^ ๐”ฐ p.1 := (mem_ball.mp (Grid_subset_ball hxE.1)).le  have h : โ€–Ks (๐”ฐ p.1) x yโ€–โ‚‘ โ‰ค 2 ^ a ^ 3 / volume (ball x (D ^ (๐”ฐ 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 ^ ๐”ฐ p.1)) โ‰ค 2 ^ a * volume (ball x (8 * D ^ ๐”ฐ 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 ^ ๐”ฐ p.1 โ‰ค 2 * (8 * D ^ ๐”ฐ p.1) :=    calc      _ โ‰ค (4 : โ„) * D ^ ๐”ฐ p.1 + 8 * D ^ ๐”ฐ p.1 := (add_le_add_iff_right _).mpr hdist_cp      _ โ‰ค _ := by linarith  convert measure_ball_le_of_dist_le' (ฮผ := volume) zero_lt_two h2  simp [As]