Bounds on saddle connections for flat spheres
Geometric Topology
2026-05-07 v2 Differential Geometry
Abstract
We consider a flat metric with conical singularities on the sphere. Under the assumption that no partial sum of angle defects is equal to , we draw on the geometry of immersed disks to obtain an explicit upper bound on the number of saddle connections with at most self-intersections. Additionally, we establish an upper bound on their lengths for a surface with a normalized area. Finally, we apply these bounds to the counting of singular trajectories in irrational polygonal billiards.
Cite
@article{arxiv.2308.08940,
title = {Bounds on saddle connections for flat spheres},
author = {Kai Fu and Guillaume Tahar},
journal= {arXiv preprint arXiv:2308.08940},
year = {2026}
}
Comments
27 pages, 17 figures, to appear in Journal of Topology