Definable sets in a hyperbolic group
Group Theory
2013-05-07 v5
Abstract
We give a description of definable sets in a free non-abelian group and in a torsion-free non-elementary hyperbolic group that follows from our work on the Tarski problems. This answers Malcev's question for . As a corollary we show that proper non-cyclic subgroups of and are not definable and prove Bestvina and Feighn's result that definable subsets in a free group are either negligible or co-negligible in their terminology.
Cite
@article{arxiv.1111.0577,
title = {Definable sets in a hyperbolic group},
author = {Olga Kharlampovich and Alexei Myasnikov},
journal= {arXiv preprint arXiv:1111.0577},
year = {2013}
}
Comments
Corollary of Theorem 3 was corrected and incorporated into Theorem 3