English

Hyperbolic quotients of projection complexes

Group Theory 2020-08-25 v2 Geometric Topology

Abstract

This paper is a continuation of our previous work with Margalit where we studied group actions on projection complexes. In that paper, we demonstrated sufficient conditions so that the normal closure of a family of subgroups of vertex stabilizers is a free product of certain conjugates of these subgroups. In this paper, we study both the quotient of the projection complex by this normal subgroup and the action of the quotient group on the quotient of the projection complex. We show that under certain conditions that the quotient complex is δ\delta-hyperbolic. Additionally, under certain circumstances, we show that if the original action on the projection complex was a non-elementary WPD action, then so is the action of the quotient group on the quotient of the projection complex. This implies that the quotient group is acylindrically hyperbolic.

Keywords

Cite

@article{arxiv.2005.14232,
  title  = {Hyperbolic quotients of projection complexes},
  author = {Matt Clay and Johanna Mangahas},
  journal= {arXiv preprint arXiv:2005.14232},
  year   = {2020}
}

Comments

16 pages, 1 figures; incorporated suggestions from referee

R2 v1 2026-06-23T15:53:41.311Z