fpvandoorn/carleson
Source indexedlemma Β· leanprover/lean4:v4.32.0
TileStructure.Forest.first_tree_pointwise
Carleson.ForestOperator.PointwiseEstimate Β· Carleson/ForestOperator/PointwiseEstimate.lean:601 to 666
Source documentation
Lemma 7.1.4
Exact Lean statement
lemma first_tree_pointwise (hu : u β t) (hL : L β π (t u)) (hx : x β L) (hx' : x' β L)
(hf : BoundedCompactSupport f) :
ββ i β t.Ο u x, β« y, (exp (.I * (-π¬ u y + Q x y + π¬ u x - Q x x)) - 1) * Ks i x y * f yββ β€
C7_1_4 a * maximalFunction volume π cπ rπ 1 (approxOnCube (π (t u)) (βf Β·β)) x'Complete declaration
Lean source
Full Lean sourceLean 4
lemma first_tree_pointwise (hu : u β t) (hL : L β π (t u)) (hx : x β L) (hx' : x' β L) (hf : BoundedCompactSupport f) : ββ i β t.Ο u x, β« y, (exp (.I * (-π¬ u y + Q x y + π¬ u x - Q x x)) - 1) * Ks i x y * f yββ β€ C7_1_4 a * maximalFunction volume π cπ rπ 1 (approxOnCube (π (t u)) (βf Β·β)) x' := by let _ : MulPosReflectLE β := inferInstance -- perf: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/performance.20example.20with.20type-class.20inference let _ : PosMulReflectLE β := inferInstance -- perf: https://leanprover.zulipchat.com/#narrow/channel/287929-mathlib4/topic/performance.20example.20with.20type-class.20inference set g := approxOnCube (π (t u)) (βf Β·β) let q (y) := -π¬ u y + Q x y + π¬ u x - Q x x rcases (t.Ο u x).eq_empty_or_nonempty with hΟ | hΟ; Β· simp [hΟ] have : β s β t.Ο u x, ββ« y, (cexp (I * (q y)) - 1) * Ks s x y * f yββ β€ β«β» y, β(exp (I * q y) - 1) * Ks s x y * f yββ := fun s hs β¦ (enorm_integral_le_lintegral_enorm _).trans (by simp) conv_lhs => enter [1, 2, s, 2, y] rw [β Complex.ofReal_neg, β Complex.ofReal_add, β Complex.ofReal_add, β Complex.ofReal_sub] refine (enorm_sum_le _ _).trans <| ((t.Ο u x).sum_le_sum this).trans ?_ suffices β s β t.Ο u x, β«β» y, β(exp (I * q y) - 1) * Ks s x y * f yββ β€ (5 * 2 ^ ((π + 4) * a ^ 3) * maximalFunction volume π cπ rπ 1 g x') * 2 ^ (s - t.ΟMax u x hΟ) by apply ((t.Ο u x).sum_le_sum this).trans rw [β Finset.mul_sum] apply le_trans <| mul_le_mul_right (L7_1_4_sum hΟ) _ rw [mul_comm _ 2, β mul_assoc, β mul_assoc, C7_1_4] gcongr; norm_num intro s hs have eq1 : β«β» y, β(exp (I * q y) - 1) * Ks s x y * f yββ = β«β» y in ball x (D ^ s / 2), β(exp (I * q y) - 1) * Ks s x y * f yββ := by rw [β lintegral_indicator measurableSet_ball]; congr! 2 with y symm; rw [indicator_apply_eq_self]; intro my suffices Ks s x y = 0 by simp [this] contrapose! my; apply dist_mem_Ioo_of_Ks_ne_zero at my rw [mem_Ioo] at my; rw [mem_ball']; exact my.2 have eq2 : β«β» y in ball x (D ^ s / 2), β(exp (I * q y) - 1) * Ks s x y * f yββ β€ 5 * 2 ^ (s - ΟMax t u x β¨s, hsβ©) * (2 ^ ((π + 3) * a ^ 3) / volume (ball x (D ^ s))) * β«β» y in ball x (D ^ s / 2), βf yββ := by convert! (lintegral_mono (L7_1_4_integrand_bound f hu hs)).trans ?_ Β· norm_cast Β· rw [lintegral_const_mul'' _ hf.aestronglyMeasurable.enorm.restrict] apply le_of_eq_of_le eq1 β eq2.trans rw [β mul_rotate _ (5 * 2 ^ ((π + 4) * a ^ 3)), β mul_assoc, mul_comm _ 5] simp_rw [mul_assoc]; gcongr _ * (_ * ?_) rw [show (π + 4) * a ^ 3 = (π + 3) * a ^ 3 + a ^ 3 by ring, pow_add, mul_assoc, ENNReal.mul_comm_div] gcongr have β¨pβ, pβu, xpβ, hpββ© := t.exists_p_of_mem_Ο u x hs have ball_subset : ball (π pβ) (16 * D ^ s) β ball x ((2 ^ 5) * D ^ s) := by apply ball_subset_ball' calc _ β€ (16 : β) * D ^ s + 4 * D ^ π° pβ := add_le_add_right (mem_ball'.mp (Grid_subset_ball xpβ.1)).le _ _ = 16 * D ^ s + 4 * D ^ s := by nth_rw 3 [β hpβ] _ β€ _ := by linarith only [defaultD_pow_pos a s] calc _ β€ 2 ^ (5 * a) * ((β«β» y in ball x (D ^ s / 2), βf yββ) / volume (ball (π pβ) (16 * D ^ s))) := by rw [mul_comm, ENNReal.div_mul _ (.inr (by positivity)) (.inr (by finiteness))]; gcongr refine ENNReal.div_le_of_le_mul' ((measure_mono ball_subset).trans ?_) convert! measure_ball_two_le_same_iterate (ΞΌ := volume) x (D ^ s) 5 using 2 simp [mul_comm 5 a, pow_mul] _ β€ _ := by gcongr ?_ * ?_ Β· apply pow_right_monoβ one_le_two rw [pow_succ a 2, mul_le_mul_iff_leftβ (a_pos X)] nlinarith [four_le_a X] Β· refine le_trans ?_ (L7_1_4_laverage_le_MB hL hx hx' g pβu xpβ) rw [hpβ]; gcongr ?_ / _ rw [β hpβ]; exact L7_1_4_integral_le_integral hu hf pβu xpβ