English

Fundamental domains for quaternionic S-arithmetic groups over totally real fields

Number Theory 2025-10-13 v1

Abstract

Let BB be a totally-definite quaternion algebra over a totally real field FF, let p\mathfrak{p} be a prime ideal of FF, and let Γ\Gamma be the group of reduced norm-11 elements of an Eichler OF[1/p]\mathcal{O}_F[1/\mathfrak{p}]-order RR inside BB. We give an algorithm to compute the fundamental domain for the action of Γ\Gamma on the Bruhat-Tits tree of GL2(Fp)\operatorname{GL}_2(F_\mathfrak{p}). Using this, we tabulate Shimura curves of genus up to 33 over any totally real field which can be p\mathfrak{p}-adically uniformized for some prime p\mathfrak{p}.

Keywords

Cite

@article{arxiv.2510.09356,
  title  = {Fundamental domains for quaternionic S-arithmetic groups over totally real fields},
  author = {Marc Masdeu and Eloi Torrents},
  journal= {arXiv preprint arXiv:2510.09356},
  year   = {2025}
}

Comments

14 pages, comments welcome

R2 v1 2026-07-01T06:29:23.123Z