OAI/Analysis/KadisonKastler/CauchyFourier.lean
2 declarations, 0 contain sorry, 0 declared as axioms
The scalar Cauchy transform by Fourier inversion
- theorem
OAI.KadisonKastler.fourier_laplaceKernel_cauchyline 17Source documentation
In mathlib's Fourier convention the transform of the two-sided exponential is exactly the normalized Cauchy density.
theorem fourier_laplaceKernel_cauchy {γ : NNReal} (hγ : 0 < γ) (ξ : ℝ) : 𝓕 (laplaceKernel (2 * Real.pi * γ)) ξ = (cauchyPDFReal 0 γ ξ : ℂ) := by …Mentions: OAI.KadisonKastler.laplaceKernel
- theorem
OAI.KadisonKastler.fourierInv_cauchyPDFRealline 32Source documentation
The inverse transform of the Cauchy density is the two-sided exponential. All integrability hypotheses follow from proved library results and the explicit transform above.
theorem fourierInv_cauchyPDFReal {γ : NNReal} (hγ : 0 < γ) (t : ℝ) : 𝓕⁻ (fun x : ℝ => (cauchyPDFReal 0 γ x : ℂ)) t = laplaceKernel (2 * Real.pi * γ) t := by …Mentions: OAI.KadisonKastler.laplaceKernel