Global and local maximizers for some Fourier extension estimates on the sphere

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Ciccone, Valentina, Sousa, Mateus
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912559093776384
author Ciccone, Valentina
Sousa, Mateus
author_facet Ciccone, Valentina
Sousa, Mateus
contents In this note, we study maximizers for Fourier extension inequalities on the sphere. We prove that constant functions are local maximizers for the $L^p(\mathbb{S}^{d-1})$ to $L^p(\mathbb{R}^d)$ Fourier extension estimates in the same range of exponents $p$ for which they are global maximizers for the $L^2(\mathbb{S}^{d-1})$ to $L^p_{rad}L^2_{ang}(\mathbb{R}^d)$ mixed-norm Fourier extension inequalities. Moreover, in the case of low dimensions, we improve the range of exponents for which constant functions are known to be the unique global maximizers for the $L^2(\mathbb{S}^{d-1})$ to $L^p_{rad}L^2_{ang}(\mathbb{R}^d)$ mixed-norm Fourier extension estimate on the sphere, covering, for the case of dimensions $d=2,3$, the entire Stein-Tomas range. This is achieved by establishing novel hierarchies between certain weighted norms of Bessel functions.
format Preprint
id arxiv_https___arxiv_org_abs_2312_07309
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Global and local maximizers for some Fourier extension estimates on the sphere
Ciccone, Valentina
Sousa, Mateus
Classical Analysis and ODEs
42B10
In this note, we study maximizers for Fourier extension inequalities on the sphere. We prove that constant functions are local maximizers for the $L^p(\mathbb{S}^{d-1})$ to $L^p(\mathbb{R}^d)$ Fourier extension estimates in the same range of exponents $p$ for which they are global maximizers for the $L^2(\mathbb{S}^{d-1})$ to $L^p_{rad}L^2_{ang}(\mathbb{R}^d)$ mixed-norm Fourier extension inequalities. Moreover, in the case of low dimensions, we improve the range of exponents for which constant functions are known to be the unique global maximizers for the $L^2(\mathbb{S}^{d-1})$ to $L^p_{rad}L^2_{ang}(\mathbb{R}^d)$ mixed-norm Fourier extension estimate on the sphere, covering, for the case of dimensions $d=2,3$, the entire Stein-Tomas range. This is achieved by establishing novel hierarchies between certain weighted norms of Bessel functions.
title Global and local maximizers for some Fourier extension estimates on the sphere
topic Classical Analysis and ODEs
42B10
url https://arxiv.org/abs/2312.07309