Skip to main content
fpvandoorn/carleson
Source indexedtheorem · leanprover/lean4:v4.32.0

antichain_operator_le_volume

Carleson.Antichain.AntichainOperator · Carleson/Antichain/AntichainOperator.lean:464 to 476

Source documentation

Version of the antichain operator theorem, but controlling the integral of the norm instead of the integral of the function multiplied by another function, and with the upper bound in terms of volume F and volume G.

Exact Lean statement

theorem antichain_operator_le_volume {A : Set X} (h𝔄 : IsAntichain (· ≤ ·) 𝔄)
    (hf : Measurable f) (hfF : ∀ x, ‖f x‖ ≤ F.indicator 1 x) (hA : A ⊆ G) :
    ∫⁻ x in A, ‖carlesonSum 𝔄 f x‖ₑ ≤
    C2_0_3 a nnq * dens₁ 𝔄 ^ ((q - 1) / (8 * a ^ 4)) * dens₂ 𝔄 ^ (q⁻¹ - 2⁻¹) *
    volume F ^ (1/2 : ℝ) * volume G ^ (1/2 : ℝ)

Complete declaration

Lean source

Canonical source
Full Lean sourceLean 4
theorem antichain_operator_le_volume {A : Set X} (h𝔄 : IsAntichain (·  ·) 𝔄)    (hf : Measurable f) (hfF :  x, ‖f x‖  F.indicator 1 x) (hA : A  G) :    ∫⁻ x in A, ‖carlesonSum 𝔄 f x‖ₑ     C2_0_3 a nnq * dens₁ 𝔄 ^ ((q - 1) / (8 * a ^ 4)) * dens₂ 𝔄 ^ (q⁻¹ - 2⁻¹) *    volume F ^ (1/2 : ) * volume G ^ (1/2 : ) := by  apply (antichain_operator' h𝔄 hf hfF hA).trans  gcongr  calc  _  eLpNorm (F.indicator (fun x  1) : X  ) 2 volume :=    eLpNorm_mono (fun x  (hfF x).trans (le_abs_self _))  _  _ := by    rw [eLpNorm_indicator_const measurableSet_F (by norm_num) (by norm_num)]    simp