English

Limits of conjugacy classes under iterates of Hyperbolic elements of $\mathsf{Out(\mathbb{F})}$

Group Theory 2018-02-16 v3

Abstract

For a free group F\mathbb{F} of finite rank such that rank(F)3\text{rank}(\mathbb{F})\geq 3, we prove that the set of weak limits of a conjugacy class in F\mathbb{F} under iterates of some hyperbolic ϕOut(F)\phi\in\mathsf{Out(\mathbb{F})} is equal to the collection of generic leaves and singular lines of ϕ\phi. As an application we describe the ending lamination set for a hyperbolic extension of F\mathbb{F} by a hyperbolic subgroup of Out(F)\mathsf{Out(\mathbb{F})} in a new way and use it to prove results about Cannon-Thurston maps for such extensions. We also use it to derive conditions for quasiconvexity of finitely generated, infinite index subgroups of F\mathbb{F} in the extension group. These results generalize similar results obtained by Mahan Mj, Kapovich-Lustig and use different techniques.

Keywords

Cite

@article{arxiv.1709.09024,
  title  = {Limits of conjugacy classes under iterates of Hyperbolic elements of $\mathsf{Out(\mathbb{F})}$},
  author = {Pritam Ghosh},
  journal= {arXiv preprint arXiv:1709.09024},
  year   = {2018}
}

Comments

Several typos corrected; a misleading/ conflicting notation has been changed in the statement of the main theorem and the results which depend on it; introduction reorganized; references updated