fpvandoorn/carleson
Source indexedlemma · leanprover/lean4:v4.32.0
continuous_carlesonOperatorIntegrand
Carleson.MetricCarleson.Basic · Carleson/MetricCarleson/Basic.lean:454 to 471
Mathematical statement
Exact Lean statement
lemma continuous_carlesonOperatorIntegrand (mf : Measurable f) (nf : (‖f ·‖) ≤ 1) (hR₁ : 0 < R₁) :
Continuous (carlesonOperatorIntegrand K · R₁ R₂ f x)Complete declaration
Lean source
Full Lean sourceLean 4
lemma continuous_carlesonOperatorIntegrand (mf : Measurable f) (nf : (‖f ·‖) ≤ 1) (hR₁ : 0 < R₁) : Continuous (carlesonOperatorIntegrand K · R₁ R₂ f x) := by rcases le_or_gt R₂ R₁ with hR₂ | hR₂ · unfold carlesonOperatorIntegrand; rw [Annulus.oo_eq_empty (by simp [hR₂])] simp_rw [setIntegral_empty]; exact continuous_const lift R₁ to ℝ≥0 using hR₁.le lift R₂ to ℝ≥0 using (hR₁.trans hR₂).le rw [NNReal.coe_pos] at hR₁; rw [NNReal.coe_lt_coe] at hR₂ have R₂pos := hR₁.trans hR₂ rw [continuous_iff]; intro ϑ ε εpos let C₁ := As (defaultA a) (dist o x + R₂ + dist o x) have C₁pos : 0 < C₁ := by unfold C₁ As; norm_cast; positivity have C₂pos : 0 < C3_0_1 a R₁ R₂ := by rw [C3_0_1]; positivity refine ⟨ε / (C₁ * C3_0_1 a R₁ R₂), by positivity, fun θ db ↦ ?_⟩ calc _ ≤ _ := dist_carlesonOperatorIntegrand_le mf nf hR₁ _ ≤ C3_0_1 a R₁ R₂ * C₁ * dist θ ϑ := by rw [mul_assoc]; gcongr; apply cdist_le_dist; positivity _ < _ := by rwa [← lt_div_iff₀' (by positivity), mul_comm]