English

Closed geodesics on semi-arithmetic Riemann surfaces

Geometric Topology 2020-09-02 v2 Metric Geometry Number Theory

Abstract

In this article, we study geometric aspects of semi-arithmetic Riemann surfaces by means of number theory and hyperbolic geometry. First, we show the existence of infinitely many semi-arithmetic Riemann surfaces of various shapes and prove that their systoles are dense in the positive real numbers. Furthermore, this leads to a construction, for each genus g2,g \geq 2, of infinite families of semi-arithmetic surfaces with pairwise distinct invariant trace fields, giving a negative answer to a conjecture of B. Jeon. Finally, for any semi-arithmetic surface we find a sequence of congruence coverings with logarithmic systolic growth and, for the special case of surfaces admitting modular embedding, we are able to exhibit explicit constants.

Keywords

Cite

@article{arxiv.2004.13683,
  title  = {Closed geodesics on semi-arithmetic Riemann surfaces},
  author = {Gregory Cosac and Cayo Dória},
  journal= {arXiv preprint arXiv:2004.13683},
  year   = {2020}
}
R2 v1 2026-06-23T15:09:36.911Z