English

Expansion in SL_d(Z/qZ), q arbitrary

Group Theory 2012-05-15 v1 Combinatorics Dynamical Systems

Abstract

Let S be a fixed finite symmetric subset of SL_d(Z), and assume that it generates a Zariski-dense subgroup G. We show that the Cayley graphs of pi_q(G) with respect to the generating set pi_q(S) form a family of expanders, where pi_q is the projection map Z->Z/qZ.

Keywords

Cite

@article{arxiv.1006.3365,
  title  = {Expansion in SL_d(Z/qZ), q arbitrary},
  author = {Jean Bourgain and Péter P. Varjú},
  journal= {arXiv preprint arXiv:1006.3365},
  year   = {2012}
}