English

A Beurling-Helson type theorem for modulation spaces

Classical Analysis and ODEs 2008-01-10 v1 Functional Analysis

Abstract

We prove a Beurling-Helson type theorem on modulation spaces. More precisely, we show that the only C1\mathcal{C}^{1} changes of variables that leave invariant the modulation spaces \Mp,q(\rd)\M{p,q}(\rd) are affine functions on \rd\rd. A special case of our result involving the Sj\"ostrand algebra was considered earlier by A. Boulkhemair.

Keywords

Cite

@article{arxiv.0801.1338,
  title  = {A Beurling-Helson type theorem for modulation spaces},
  author = {Kasso A Okoudjou},
  journal= {arXiv preprint arXiv:0801.1338},
  year   = {2008}
}
R2 v1 2026-06-21T10:01:04.296Z