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

TileStructure.Forest.e764_postCS

Carleson.ForestOperator.RemainingTiles · Carleson/ForestOperator/RemainingTiles.lean:627 to 695

Source documentation

Equation (7.6.4) of Lemma 7.6.2 (after applying Cauchy–Schwarz and simplification).

Exact Lean statement

lemma e764_postCS (hu₁ : u₁ ∈ t) (hu₂ : u₂ ∈ t) (hu : u₁ ≠ u₂) (h2u : 𝓘 u₁ ≤ 𝓘 u₂)
    (hf : BoundedCompactSupport f) :
    eLpNorm (approxOnCube (𝓙₆ t u₁) (‖adjointCarlesonSum (t u₂ \ 𝔖₀ t u₁ u₂) f ·‖)) 2 volume ≤
    C2_1_3 a * 2 ^ (11 * a + 2) *
    (∑ k ∈ Finset.Icc ⌊C7_6_3 a n⌋ (2 * S), (D : ℝ≥0∞) ^ (-k * κ / 2)) *
    eLpNorm ((𝓘 u₁ : Set X).indicator (maximalFunction volume 𝓑 c𝓑 r𝓑 1 f ·)) 2 volume

Complete declaration

Lean source

Canonical source
Full Lean sourceLean 4
lemma e764_postCS (hu₁ : u₁  t) (hu₂ : u₂  t) (hu : u₁  u₂) (h2u : 𝓘 u₁  𝓘 u₂)    (hf : BoundedCompactSupport f) :    eLpNorm (approxOnCube (𝓙₆ t u₁) (‖adjointCarlesonSum (t u₂ \ 𝔖₀ t u₁ u₂) f ·‖)) 2 volume     C2_1_3 a * 2 ^ (11 * a + 2) *    (∑ k  Finset.Icc ⌊C7_6_3 a n⌋ (2 * S), (D : 0∞) ^ (-k * κ / 2)) *    eLpNorm ((𝓘 u₁ : Set X).indicator (maximalFunction volume 𝓑 c𝓑 r𝓑 1 f ·)) 2 volume := by  have aem_MB : AEMeasurable (maximalFunction volume 𝓑 c𝓑 r𝓑 1 f) volume :=    measurable_maximalFunction.aemeasurable  classical  calc    _  _ := e764_preCS hu₁ hu₂ hu h2u hf    _ = C2_1_3 a * 2 ^ (4 * a) * ∑ k  Finset.Icc ⌊C7_6_3 a n⌋ (2 * S),        (∑ J  (𝓙₆ t u₁).toFinset, (volume (J : Set X))⁻¹ *        (∫⁻ y in J, maximalFunction volume 𝓑 c𝓑 r𝓑 1 f y *        ∑ I with s I = s J - k  Disjoint (I : Set X) (𝓘 u₁)           ¬Disjoint ↑J (ball (c I) (8 * D ^ s I)),        (ball (c I) (8 * D ^ s I)).indicator 1 y) ^ 2) ^ (2 : )⁻¹ := by      congr! with k mk J mJ      rw [ lintegral_finsetSum']; swap      · fun_prop (discharger := measurability)      congr with y; rw [mul_comm, Finset.sum_mul]    _  C2_1_3 a * 2 ^ (4 * a) * ∑ k  Finset.Icc ⌊C7_6_3 a n⌋ (2 * S),        (∑ J  (𝓙₆ t u₁).toFinset, (∫⁻ y in J, maximalFunction volume 𝓑 c𝓑 r𝓑 1 f y ^ 2) *        (⨍⁻ y in J, (∑ I : Grid X with s I = s J - k  Disjoint (I : Set X) (𝓘 u₁)           ¬Disjoint ↑J (ball (c I) (8 * D ^ s I)),        (ball (c I) (8 * D ^ s I)).indicator 1 y) ^ 2 ∂volume)) ^ (2 : )⁻¹ := by      gcongr _ * ∑ k  _, (∑ J  _, ?_) ^ _ with k mk J mJ      rw [setLAverage_eq, ENNReal.div_eq_inv_mul,  mul_assoc, mul_comm _ _⁻¹, mul_assoc]      gcongr; apply ENNReal.sq_lintegral_mul_le_mul_lintegral_sq aem_MB.restrict -- Cauchy–Schwarz      fun_prop (discharger := measurability)    _  C2_1_3 a * 2 ^ (4 * a) * ∑ k  Finset.Icc ⌊C7_6_3 a n⌋ (2 * S),        (∑ J  (𝓙₆ t u₁).toFinset,        (∫⁻ y in J, maximalFunction volume 𝓑 c𝓑 r𝓑 1 f y ^ 2) * C7_6_4 a k) ^ (2 : )⁻¹ := by      gcongr with k mk J mJ; rw [mem_toFinset] at mJ; exact square_function_count mJ    _  C2_1_3 a * 2 ^ (4 * a) *        ∑ k  Finset.Icc ⌊C7_6_3 a n⌋ (2 * S),        2 ^ (7 * a + 2) * D ^ (-k * κ / 2) * (∑ J  (𝓙₆ t u₁).toFinset,        ∫⁻ y in J, maximalFunction volume 𝓑 c𝓑 r𝓑 1 f y ^ 2) ^ (2 : )⁻¹ := by      gcongr with k mk      rw [ Finset.sum_mul, mul_comm _ (C7_6_4 a k : 0∞),        ENNReal.mul_rpow_of_nonneg _ _ (by positivity)]      gcongr      rw [C7_6_4, NNReal.mul_rpow, show (8 : 0) = 2 ^ (3 : ) by norm_num,  NNReal.rpow_mul,         mul_assoc,  NNReal.rpow_intCast,  NNReal.rpow_mul,        ENNReal.rpow_ofNNReal (by positivity), NNReal.mul_rpow,  NNReal.rpow_mul,         NNReal.rpow_add two_ne_zero,  NNReal.rpow_mul, ENNReal.coe_mul,        ENNReal.coe_rpow_of_ne_zero two_ne_zero,  show (2 : 0∞) = (2 : 0) by rfl,        ENNReal.coe_rpow_of_ne_zero (by norm_cast; unfold defaultD; positivity),        show ((D : 0) : 0∞) = (D : 0∞) by rfl, Int.cast_neg, div_eq_mul_inv,         ENNReal.rpow_natCast]      gcongr      · exact one_le_two      · rw [add_assoc, add_mul, Nat.cast_add, Nat.cast_mul, show (14 * a * 2⁻¹ : ) = 7 * a by ring,          Nat.cast_ofNat]        gcongr        calc          _  (1 + 3 * 1) * (2 : )⁻¹ := by gcongr; exact κ_le_one          _ = _ := by norm_num    _ = _ := by      rw [ Finset.sum_mul,  Finset.mul_sum,  mul_assoc,  mul_assoc, mul_assoc _ (_ ^ _) (_ ^ _),         pow_add, show 4 * a + (7 * a + 2) = 11 * a + 2 by lia]      congr; rw [ lintegral_biUnion_finset _ fun _ _  coeGrid_measurable]; swap      · rw [coe_toFinset]; exact pairwiseDisjoint_𝓙₆      simp_rw [mem_toFinset, union_𝓙₆ hu₁,  lintegral_indicator coeGrid_measurable,        eLpNorm_eq_lintegral_rpow_enorm_toReal two_ne_zero ENNReal.ofNat_ne_top,        ENNReal.toReal_ofNat, one_div, show (2 : ) = (2 : ) by rfl, ENNReal.rpow_natCast,        enorm_eq_self]      congr! with x      simp_rw [sq,  inter_indicator_mul, inter_self]