OAI/NumberTheory/CubicMoment/Estimates/FourierTwoDerivatives.lean
5 declarations, 0 contain sorry, 0 declared as axioms
Two integrable derivatives give the Fourier L1 bound needed for the fixed inverse-square extension in the far-cell argument.
- lemma
OAI.CubicFirstMoment.norm_fourier_le_l1line 14 - lemma
OAI.CubicFirstMoment.fourier_second_derivline 20 - lemma
OAI.CubicFirstMoment.fourier_two_derivative_boundline 28 - theorem
OAI.CubicFirstMoment.integrable_fourier_of_two_derivativesline 47 - theorem
OAI.CubicFirstMoment.fourier_dilation_l1line 61Source documentation
Dilation costs no Fourier L1 mass, including the exact Jacobian.
theorem fourier_dilation_l1 (f : ℝ → ℂ) {J : ℝ} (hJ : 0 < J) : (∫ t : ℝ, ‖𝓕 (fun x => f (J*x)) t‖) = ∫ t : ℝ, ‖𝓕 f t‖ := by …