Property (T) in random quotients of hyperbolic groups at densities above 1/3
Group Theory
2022-03-28 v2
Abstract
We study random quotients of a fixed non-elementary hyperbolic group in the Gromov density model. Let be a finite presentation of a non-elementary hyperbolic group, and let be the set of elements of norm between and in . A random quotient at density and length -near is defined by killing a uniformly randomly chosen set of words in , where . We prove that for any d>1/3, such a quotient has Property (T) with probability tending to as tends to infinity. This result answers a question of Gromov--Ollivier and strengthens a theorem of \.{Z}uk (c.f Kotowski--Kotowski).
Keywords
Cite
@article{arxiv.2202.12318,
title = {Property (T) in random quotients of hyperbolic groups at densities above 1/3},
author = {Calum J. Ashcroft},
journal= {arXiv preprint arXiv:2202.12318},
year = {2022}
}
Comments
39 pages. V2: corrected statement and proof of Theorem A, introduced Theorem B, added appropriate reference for Lemma 4.4