Exponential bases for parallelepipeds with frequencies lying in a prescribed lattice

Fuente: arXiv
Salvato in:
Dettagli Bibliografici
Autori principali: Lee, Dae Gwan, Pfander, Goetz E., Walnut, David
Natura: Preprint
Pubblicazione: 2024
Soggetti:
Accesso online:
Tags: Aggiungi Tag
Nessun Tag, puoi essere il primo ad aggiungerne!!
_version_ 1866914712671748096
author Lee, Dae Gwan
Pfander, Goetz E.
Walnut, David
author_facet Lee, Dae Gwan
Pfander, Goetz E.
Walnut, David
contents The existence of a Fourier basis with frequencies in $\mathbb{R}^d$ for the space of square integrable functions supported on a given parallelepiped in $\mathbb{R}^d$, has been well understood since the 1950s. In a companion paper, we derived necessary and sufficient conditions for a parallelepiped in $\mathbb{R}^d$ to permit an orthogonal basis of exponentials with frequencies constrained to be a subset of a prescribed lattice in $\mathbb{R}^d$, a restriction relevant in many applications. In this paper, we investigate analogous conditions for parallelepipeds that permit a Riesz basis of exponentials with the same constraints on the frequencies. We provide a sufficient condition on the parallelepiped for the Riesz basis case which directly extends one of the necessary and sufficient conditions obtained in the orthogonal basis case. We also provide a sufficient condition which constrains the spectral norm of the matrix generating the parallelepiped, instead of constraining the structure of the matrix.
format Preprint
id arxiv_https___arxiv_org_abs_2401_08042
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Exponential bases for parallelepipeds with frequencies lying in a prescribed lattice
Lee, Dae Gwan
Pfander, Goetz E.
Walnut, David
Classical Analysis and ODEs
42B05, 42C15
The existence of a Fourier basis with frequencies in $\mathbb{R}^d$ for the space of square integrable functions supported on a given parallelepiped in $\mathbb{R}^d$, has been well understood since the 1950s. In a companion paper, we derived necessary and sufficient conditions for a parallelepiped in $\mathbb{R}^d$ to permit an orthogonal basis of exponentials with frequencies constrained to be a subset of a prescribed lattice in $\mathbb{R}^d$, a restriction relevant in many applications. In this paper, we investigate analogous conditions for parallelepipeds that permit a Riesz basis of exponentials with the same constraints on the frequencies. We provide a sufficient condition on the parallelepiped for the Riesz basis case which directly extends one of the necessary and sufficient conditions obtained in the orthogonal basis case. We also provide a sufficient condition which constrains the spectral norm of the matrix generating the parallelepiped, instead of constraining the structure of the matrix.
title Exponential bases for parallelepipeds with frequencies lying in a prescribed lattice
topic Classical Analysis and ODEs
42B05, 42C15
url https://arxiv.org/abs/2401.08042