English

Bounded common fundamental domains for two lattices

Classical Analysis and ODEs 2025-12-01 v2 Metric Geometry

Abstract

We prove that for any two lattices L,MRdL, M \subseteq \mathbb{R}^d of the same volume there exists a measurable, bounded, common fundamental domain of them. In other words, there exists a bounded measurable set ERdE \subseteq \mathbb{R}^d such that EE tiles Rd\mathbb{R}^d when translated by LL or by MM. In fact, the set EE can be taken to be a finite union of polytopes. A consequence of this is that the indicator function of EE forms a Weyl--Heisenberg (Gabor) orthogonal basis of L2(Rd)L^2(\mathbb{R}^d) when translated by LL and modulated by MM^*, the dual lattice of MM.

Keywords

Cite

@article{arxiv.2507.00604,
  title  = {Bounded common fundamental domains for two lattices},
  author = {Sigrid Grepstad and Mihail N. Kolountzakis},
  journal= {arXiv preprint arXiv:2507.00604},
  year   = {2025}
}

Comments

13 pages

R2 v1 2026-07-01T03:41:17.436Z