English

Not all finitely generated groups have universal acylindrical actions

Group Theory 2016-10-14 v3 Geometric Topology

Abstract

The class of acylindrically hyperbolic groups, which are groups that admit a certain type of non-elementary action on a hyperbolic space, contains many interesting groups such as non-exceptional mapping class groups and Out(Fn)\operatorname{Out}(\mathbb F_n) for n2n\geq 2. In such a group, a generalized loxodromic element is one that is loxodromic for some acylindrical action of the group on a hyperbolic space. Osin asks whether every finitely generated group has an acylindrical action on a hyperbolic space for which all generalized loxodromic elements are loxodromic. We answer this question in the negative, using Dunwoody's example of an inaccessible group as a counterexample.

Keywords

Cite

@article{arxiv.1505.02990,
  title  = {Not all finitely generated groups have universal acylindrical actions},
  author = {Carolyn R. Abbott},
  journal= {arXiv preprint arXiv:1505.02990},
  year   = {2016}
}

Comments

6 pages

R2 v1 2026-06-22T09:32:39.490Z