English

Rotation sets and axes in the fine curve graph for torus homeomorphisms

Group Theory 2025-11-25 v2 Dynamical Systems

Abstract

We expand the dictionary between the action of a torus homeomorphism on the fine curve graph and its rotation set. More precisely, we show that the fixed points at infinity of a loxodromic element determine the rotation set up to scale. A key ingredient is a metric version of the classical WPD property from geometric group theory. As a consequence we find new stable criteria for positive scl, and for two homeomorphisms to generate a free group, and we provide a Tits alternative for groups of torus homeomorphisms.

Keywords

Cite

@article{arxiv.2509.26156,
  title  = {Rotation sets and axes in the fine curve graph for torus homeomorphisms},
  author = {Sebastian Hensel and Frédéric Le Roux},
  journal= {arXiv preprint arXiv:2509.26156},
  year   = {2025}
}

Comments

68 pages, 19 figures