English

Minimal Sets of Generators for Big Mapping Class Groups

Geometric Topology 2025-12-22 v1

Abstract

Let S(n)S(n) be the infinite-type surface with infinite genus and nNn \in \mathbb{N} ends, all of which are accumulated by genus. The mapping class group of this surface, mod(S(n))\mod(S(n)), is a Polish group that is not countably generated, but it is countably topologically generated. This paper focuses on finding minimal sets of generators for mod(S(n))\mod(S(n)). We show that for n8n \ge 8, mod(S(n))\mod(S(n)) is topologically generated by three elements, and for n3n \ge 3, mod(S(n))\mod(S(n)) is topologically generated by four elements. We also establish a generating set of two elements for the Loch Ness Monster surface (n=1n=1) and a generating set of three elements for the Jacob's Ladder surface (n=2n=2).

Keywords

Cite

@article{arxiv.2512.17465,
  title  = {Minimal Sets of Generators for Big Mapping Class Groups},
  author = {Tülin Altunöz and Celal Can Bellek and Emir Gül and Mehmetcik Pamuk and Oğuz Yıldız},
  journal= {arXiv preprint arXiv:2512.17465},
  year   = {2025}
}
R2 v1 2026-07-01T08:33:15.145Z