English

Zariski Closures and Subgroup Separability

Group Theory 2018-11-14 v2 Geometric Topology

Abstract

The main result of this article is a refinement of the well-known subgroup separability results of Hall and Scott for free and surface groups. We show that for any finitely generated subgroup, there is a finite dimensional representation of the free or surface group that separates the subgroup in the induced Zariski topology. As a corollary, we establish a polynomial upper bound on the size of the quotients used to separate a finitely generated subgroup in a free or surface group.

Keywords

Cite

@article{arxiv.1510.04144,
  title  = {Zariski Closures and Subgroup Separability},
  author = {Larsen Louder and D. B. McReynolds and Priyam Patel},
  journal= {arXiv preprint arXiv:1510.04144},
  year   = {2018}
}

Comments

Final version. To appear in Selecta Math

R2 v1 2026-06-22T11:20:14.044Z