English

Remarks on compactifications of pseudofinite groups

Logic 2015-09-10 v1 General Topology Group Theory

Abstract

We discuss the Bohr compactification of a pseudofinite group, motivated by a question of Boris Zilber. Basically referring to results in the literature we point out (i) the Bohr compactification of an ultraproduct of finite simple groups is trivial, and (ii) the "definable" Bohr compactification of any pseudofinite group G, relative to a nonstandard model of set theory in which it is definable, is commutative-by-profinite.

Keywords

Cite

@article{arxiv.1509.02895,
  title  = {Remarks on compactifications of pseudofinite groups},
  author = {Anand Pillay},
  journal= {arXiv preprint arXiv:1509.02895},
  year   = {2015}
}

Comments

9 pages

R2 v1 2026-06-22T10:53:06.824Z