Paley-Wiener Type Theorems associated to Dirac Operators of Riesz-Feller type

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Bernstein, Swanhild, Faustino, Nelson
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866916783161606144
author Bernstein, Swanhild
Faustino, Nelson
author_facet Bernstein, Swanhild
Faustino, Nelson
contents This paper explores Paley-Wiener type theorems within the framework of hypercomplex variables. The investigation focuses on a space-fractional version of the Dirac operator $\mathbf{D}_θ^α$ of order $α$ and skewness $θ$. The pseudo-differential reformulation of $\mathbf{D}_θ^α$ in terms of the Riesz derivative $(-Δ)^{\fracα{2}}$ and the so-called {\textit Riesz-Hilbert transform} $H$, allows for the description of generalized Hardy spaces on the upper and lower half-spaces of $\mathbf{R}^{n+1}$, $\mathbf{R}^{n+1}_+$ resp. $\mathbb{R}^{n+1}_-$, using Lévy-Feller type semigroups generated by $-(-Δ)^{\fracα{2}}$, and the boundary values $\mathbf{f}_\pm=\frac{1}{2}\left(\mathbf{f}\pm H\mathbf{f}\right)$. Subsequently, we employ a proof strategy rooted in {\textit real Paley-Wiener methods} to demonstrate that the growth behavior of the sequences of functions $\left(\left(\mathbf{D}_θ^α\right)^k\mathbf{f}_{\pm}\right)_{k\in \mathbb{N}_0}$ effectively captures the relationship between the support of the Fourier transform $\widehat{\mathbf{f}}$ of the $L^p-$function $\mathbf{f}$, in the case where $\mathrm{supp}\widehat{\mathbf{f}}\subseteq \overline{B(0,R)}$, and the solutions of Cauchy problems equipped with the space-time operator $\partial_{x_0} + \mathbf{D}_θ^α$, which are of exponential type $R^α$. Within the developed framework, introducing a hypercomplex analog for the Bernstein spaces $B_R^p$ arises naturally, allowing for the meaningful extension of the results by Kou and Qian as well as Franklin, Hogan, and Larkin. Specifically, leveraging the established Stein-Kolmogorov inequalities for hypercomplex variables enables us to accurately determine the maximum radius $R$ for which $\operatorname{supp}\widehat{\mathbf{f}} \subseteq \overline{B(0, R)}$ holds.
format Preprint
id arxiv_https___arxiv_org_abs_2405_04989
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Paley-Wiener Type Theorems associated to Dirac Operators of Riesz-Feller type
Bernstein, Swanhild
Faustino, Nelson
Complex Variables
Functional Analysis
15A66, 30G35, 35S10, 42B10, 47A11
This paper explores Paley-Wiener type theorems within the framework of hypercomplex variables. The investigation focuses on a space-fractional version of the Dirac operator $\mathbf{D}_θ^α$ of order $α$ and skewness $θ$. The pseudo-differential reformulation of $\mathbf{D}_θ^α$ in terms of the Riesz derivative $(-Δ)^{\fracα{2}}$ and the so-called {\textit Riesz-Hilbert transform} $H$, allows for the description of generalized Hardy spaces on the upper and lower half-spaces of $\mathbf{R}^{n+1}$, $\mathbf{R}^{n+1}_+$ resp. $\mathbb{R}^{n+1}_-$, using Lévy-Feller type semigroups generated by $-(-Δ)^{\fracα{2}}$, and the boundary values $\mathbf{f}_\pm=\frac{1}{2}\left(\mathbf{f}\pm H\mathbf{f}\right)$. Subsequently, we employ a proof strategy rooted in {\textit real Paley-Wiener methods} to demonstrate that the growth behavior of the sequences of functions $\left(\left(\mathbf{D}_θ^α\right)^k\mathbf{f}_{\pm}\right)_{k\in \mathbb{N}_0}$ effectively captures the relationship between the support of the Fourier transform $\widehat{\mathbf{f}}$ of the $L^p-$function $\mathbf{f}$, in the case where $\mathrm{supp}\widehat{\mathbf{f}}\subseteq \overline{B(0,R)}$, and the solutions of Cauchy problems equipped with the space-time operator $\partial_{x_0} + \mathbf{D}_θ^α$, which are of exponential type $R^α$. Within the developed framework, introducing a hypercomplex analog for the Bernstein spaces $B_R^p$ arises naturally, allowing for the meaningful extension of the results by Kou and Qian as well as Franklin, Hogan, and Larkin. Specifically, leveraging the established Stein-Kolmogorov inequalities for hypercomplex variables enables us to accurately determine the maximum radius $R$ for which $\operatorname{supp}\widehat{\mathbf{f}} \subseteq \overline{B(0, R)}$ holds.
title Paley-Wiener Type Theorems associated to Dirac Operators of Riesz-Feller type
topic Complex Variables
Functional Analysis
15A66, 30G35, 35S10, 42B10, 47A11
url https://arxiv.org/abs/2405.04989