English

Arithmetic groups with isomorphic finite quotients

Group Theory 2011-10-25 v2

Abstract

Two finitely generated groups have the same set of finite quotients if and only if their profinite completions are isomorphic. Consider the map which sends (the isomorphism class of) an S-arithmetic group to (the isomorphism class of) its profinite completion. We show that for a wide class of S-arithmetic groups, this map is finite to one, while the the fibers are of unbounded size.

Keywords

Cite

@article{arxiv.1107.4147,
  title  = {Arithmetic groups with isomorphic finite quotients},
  author = {Menny Aka},
  journal= {arXiv preprint arXiv:1107.4147},
  year   = {2011}
}

Comments

Minor revisions. To appear in Journal of Algebra

R2 v1 2026-06-21T18:39:47.288Z