A note on separability in outer automorphism groups
Group Theory
2025-08-13 v2 Geometric Topology
Abstract
We give a criterion for separability of subgroups of certain outer automorphism groups. This answers questions of Hagen and Sisto, by strengthening and generalizing a result of theirs on mapping class groups.
Cite
@article{arxiv.2407.13824,
title = {A note on separability in outer automorphism groups},
author = {Francesco Fournier-Facio},
journal= {arXiv preprint arXiv:2407.13824},
year = {2025}
}
Comments
6 pages. v2: added Propositions 2.6 and 2.8; final version, to appear in Proceedings of the Edinburgh Mathematical Society