English

Acylindrical Hyperbolicity of Out($W_n$)

Group Theory 2020-09-22 v5

Abstract

We prove that the group of outer automorphisms of the free Coxeter group WnW_n is acylindrically hyperbolic in the sense of Osin. As an application, we observe that any CAT(0) space admitting a geometric action by Out(WnW_n) must contain a rank-one geodesic. The theorem proceeds from expanding on a well-known relationship between Out(WnW_n) and the outer automorphism group of free groups.

Keywords

Cite

@article{arxiv.1610.08005,
  title  = {Acylindrical Hyperbolicity of Out($W_n$)},
  author = {Brendan Burns Healy},
  journal= {arXiv preprint arXiv:1610.08005},
  year   = {2020}
}
R2 v1 2026-06-22T16:31:31.187Z