fpvandoorn/carleson
Source indexedlemma · leanprover/lean4:v4.32.0
MeasureTheory.eLorentzNorm'_eq_integral_distribution_rpow
Carleson.ToMathlib.MeasureTheory.Function.LorentzSeminorm.Defs · Carleson/ToMathlib/MeasureTheory/Function/LorentzSeminorm/Defs.lean:42 to 64
Mathematical statement
Exact Lean statement
lemma eLorentzNorm'_eq_integral_distribution_rpow {_ : MeasurableSpace α} {f : α → ε}
{μ : Measure α} :
eLorentzNorm' f p 1 μ = p * ∫⁻ (t : ℝ≥0), distribution f t μ ^ p.toReal⁻¹Complete declaration
Lean source
Full Lean sourceLean 4
lemma eLorentzNorm'_eq_integral_distribution_rpow {_ : MeasurableSpace α} {f : α → ε} {μ : Measure α} : eLorentzNorm' f p 1 μ = p * ∫⁻ (t : ℝ≥0), distribution f t μ ^ p.toReal⁻¹ := by unfold eLorentzNorm' simp only [inv_one, ENNReal.toReal_one, ENNReal.rpow_one, ENNReal.toReal_inv] congr rw [eLpNorm_eq_lintegral_rpow_enorm_toReal (by norm_num) (by norm_num)] rw [lintegral_withDensity_eq_lintegral_mul₀' (by measurability) (by apply aeMeasurable_withDensity_inv; apply AEMeasurable.pow_const; apply AEStronglyMeasurable.enorm; apply aestronglyMeasurable_iff_aemeasurable.mpr; apply Measurable.aemeasurable; measurability)] simp only [enorm_eq_self, ENNReal.toReal_one, ENNReal.rpow_one, Pi.mul_apply, ne_eq, one_ne_zero, not_false_eq_true, div_self] rw [lintegral_nnreal_eq_lintegral_toNNReal_Ioi, lintegral_nnreal_eq_lintegral_toNNReal_Ioi] apply setLIntegral_congr_fun measurableSet_Ioi intro x hx simp only rw [← mul_assoc, ENNReal.inv_mul_cancel, one_mul] · rw [ENNReal.coe_ne_zero] symm apply ne_of_lt rw [Real.toNNReal_pos] exact hx · exact ENNReal.coe_ne_top