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fpvandoorn/carleson
Source indexedlemma ยท leanprover/lean4:v4.32.0

Tile.I12_le'

Carleson.Antichain.TileCorrelation ยท Carleson/Antichain/TileCorrelation.lean:330 to 374

Source documentation

Inequality (6.2.28).

Exact Lean statement

lemma I12_le' {p p' : ๐”“ X} (hle : ๐”ฐ p' โ‰ค ๐”ฐ p) {g : X โ†’ โ„‚} (x1 : E p') (x2 : E p) :
    I12 p p' g x1 x2 โ‰ค
    2 ^ ((2 * ๐•” + 6 + ๐•” / 4) * a ^ 3 + 8 * a) *
      ((1 + edist_{x1.1, D ^ ๐”ฐ p'} (Q x1) (Q x2)) ^ (-(2 * a ^ 2 + a ^ 3 : โ„)โปยน)) /
    volume (ball x2.1 (D ^ ๐”ฐ p)) * โ€–g x1โ€–โ‚‘ * โ€–g x2โ€–โ‚‘

Complete declaration

Lean source

Canonical source
Full Lean sourceLean 4
lemma I12_le' {p p' : ๐”“ X} (hle : ๐”ฐ p' โ‰ค ๐”ฐ p) {g : X โ†’ โ„‚} (x1 : E p') (x2 : E p) :    I12 p p' g x1 x2 โ‰ค    2 ^ ((2 * ๐•” + 6 + ๐•” / 4) * a ^ 3 + 8 * a) *      ((1 + edist_{x1.1, D ^ ๐”ฐ p'} (Q x1) (Q x2)) ^ (-(2 * a ^ 2 + a ^ 3 : โ„)โปยน)) /    volume (ball x2.1 (D ^ ๐”ฐ p)) * โ€–g x1โ€–โ‚‘ * โ€–g x2โ€–โ‚‘ := by  have hD' : 0 < (D : โ„) ^ ๐”ฐ p' := defaultD_pow_pos a (๐”ฐ p')  have hsupp : support (correlation (๐”ฐ p') (๐”ฐ p) x1.1 x2) โІ ball x1 (D ^ ๐”ฐ p') :=    fun _ hx โ†ฆ mem_ball_of_correlation_ne_zero hx  -- For compatibility with holder_van_der_corput  have heq : 2 ^ ((2 * ๐•” + 6 + ๐•” / 4) * a ^ 3 + 8 * a) *      (1 + edist_{x1.1, D ^ ๐”ฐ p'} (Q x1) (Q x2)) ^ (-(2 * a ^ 2 + a ^ 3 : โ„)โปยน) /      volume (ball x2.1 (D ^ ๐”ฐ p)) =      (2 ^ ((2 * ๐•” + 6 + ๐•” / 4) * a ^ 3 + 8 * a)) / volume (ball x2.1 (D ^ ๐”ฐ p)) *      (1 + edist_{x1.1, D ^ ๐”ฐ p'} (Q x1) (Q x2)) ^ (-(2 * a ^ 2 + a ^ 3 : โ„)โปยน) := by    rw [ENNReal.mul_comm_div, mul_comm, mul_comm _ (2 ^ _), mul_div_assoc]  simp only [I12, enorm_mul]  gcongr  simp_rw [โ† sub_eq_neg_add]  apply (holder_van_der_corput hsupp).trans  rw [heq, edist_comm]  gcongr  ยท have hbdd := correlation_kernel_bound (a := a) (X := X) hle (xโ‚ := x1) (xโ‚‚ := x2)    have hle : C2_0_5 a * volume (ball x1.1 (D ^ ๐”ฐ p')) *        iHolENorm (correlation (๐”ฐ p') (๐”ฐ p) x1.1 x2.1) x1 (2 * D ^ ๐”ฐ p') ฯ„ โ‰ค        C2_0_5 a * volume (ball x1.1 (D ^ ๐”ฐ p')) *        (C6_2_1 a / (volume (ball x1.1 (D ^ ๐”ฐ p')) * volume (ball x2.1 (D ^ ๐”ฐ p)))) := by      gcongr    -- Note: simp, ring_nf, field_simp did not help (because we work with โ„โ‰ฅ0โˆž).    have heq : C2_0_5 a * volume (ball x1.1 (D ^ ๐”ฐ p')) *        (C6_2_1 a / (volume (ball x1.1 (D ^ ๐”ฐ p')) * volume (ball x2.1 (D ^ ๐”ฐ p)))) =        C2_0_5 a * (C6_2_1 a / volume (ball x2.1 (D ^ ๐”ฐ p))) := by      simp only [mul_assoc]      congr 1      rw [ENNReal.div_eq_inv_mul, ENNReal.mul_inv (.inr measure_ball_ne_top)        (.inl measure_ball_ne_top), โ† mul_assoc, โ† mul_assoc, ENNReal.mul_inv_cancel        (measure_ball_pos volume _ hD').ne' measure_ball_ne_top, one_mul, ENNReal.div_eq_inv_mul]    apply hle.trans    rw [heq, mul_div]    apply ENNReal.div_le_div _ le_rfl    simp only [C2_0_5, C6_2_1, ENNReal.coe_pow, ENNReal.coe_ofNat]    rw [pow_add, mul_comm]    norm_cast    gcongr    ยท exact one_le_two    ยท lia