English

The number of ends of big mapping class groups

Geometric Topology 2025-12-19 v2 Group Theory Metric Geometry

Abstract

We analyze the number of ends of the mapping class group of a stable avenue surface. We prove that the mapping class group is one-ended whenever the stable avenue surface has at least one end of discrete type. Our method is to show that the associated translatable curve graph, which is quasi-isometric to the mapping class group, is one-ended.

Keywords

Cite

@article{arxiv.2512.09776,
  title  = {The number of ends of big mapping class groups},
  author = {Josiah Oh and Yulan Qing and Xiaolei Wu},
  journal= {arXiv preprint arXiv:2512.09776},
  year   = {2025}
}