English

Normal subgroups of non-torsion multi-EGS groups

Group Theory 2025-09-11 v1

Abstract

We study the distribution of normal subgroups in non-torsion, regular branch multi-EGS groups and show that the congruence completions of such groups have bounded finite central width. In particular, we show that the profinite completion of the Fabrykowski--Gupta group acting on the pp-adic tree has central width 2 for every odd prime pp. The methods used also apply to the family of Sunic groups, which closely resemble the Grigorchuk group.

Keywords

Cite

@article{arxiv.2509.08576,
  title  = {Normal subgroups of non-torsion multi-EGS groups},
  author = {Benjamin Klopsch and Anitha Thillaisundaram},
  journal= {arXiv preprint arXiv:2509.08576},
  year   = {2025}
}

Comments

25 pages

R2 v1 2026-07-01T05:30:03.148Z