English

Compact groups with countable Engel sinks

Group Theory 2020-04-15 v3

Abstract

An Engel sink of an element gg of a group GG is a set E(g){\mathscr E}(g) such that for every xGx\in G all sufficiently long commutators [...[[x,g],g],,g][...[[x,g],g],\dots ,g] belong to E(g){\mathscr E}(g). (Thus, gg is an Engel element precisely when we can choose E(g)={1}{\mathscr E}(g)=\{ 1\}.) It is proved that if every element of a compact (Hausdorff) group GG has a countable (or finite) Engel sink, then GG has a finite normal subgroup NN such that G/NG/N is locally nilpotent. This settles a question suggested by J. S. Wilson.

Keywords

Cite

@article{arxiv.1908.11637,
  title  = {Compact groups with countable Engel sinks},
  author = {E. I. Khukhro and P. Shumyatsky},
  journal= {arXiv preprint arXiv:1908.11637},
  year   = {2020}
}

Comments

Few minor corrections added