English

Spectral multipliers on M\'etivier groups

Analysis of PDEs 2025-02-11 v2 Functional Analysis

Abstract

We prove an LpL^p-spectral multiplier theorem under the sharp regularity condition s>d1/p1/2s > d\left|1/p - 1/2\right| for sub-Laplacians on M\'etivier groups. The proof is based on a restriction type estimate which, at first sight, seems to be suboptimal for proving sharp spectral multiplier results, but turns out to be surprisingly effective. This is achieved by exploiting the structural property that for any M\'etivier group the first layer of any stratification of its Lie algebra is typically much larger than the second layer, a phenomenon closely related to Radon-Hurwitz numbers.

Keywords

Cite

@article{arxiv.2412.07920,
  title  = {Spectral multipliers on M\'etivier groups},
  author = {Lars Niedorf},
  journal= {arXiv preprint arXiv:2412.07920},
  year   = {2025}
}

Comments

This paper is Part 2 of the paper previously submitted as arXiv:2304.12960. The original submission has been split into two separate papers to provide a clearer presentation of the results. Part 1 is available as a revised submission at arXiv:2304.12960. Added a funding acknowledgment in the latest version

R2 v1 2026-06-28T20:30:09.405Z