Saved in:
Bibliographic Details
Main Authors: Di Bartolo, Alfonso, Ersoy, Kıvanç, Falcone, Giovanni
Format: Preprint
Published: 2026
Subjects:
Online Access:https://arxiv.org/abs/2604.01011
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866915906020442112
author Di Bartolo, Alfonso
Ersoy, Kıvanç
Falcone, Giovanni
author_facet Di Bartolo, Alfonso
Ersoy, Kıvanç
Falcone, Giovanni
contents Thompson proved that every finite group admitting a fixed-point-free automorphism of prime order is nilpotent, and Kegel showed that the same conclusion holds for finite groups admitting a splitting automorphism of prime order. Motivated by these results, Sozutov asked whether a \(p'\)-group admitting a splitting automorphism of prime order is locally nilpotent if \[ \langle g, g^φ, \dots, g^{φ^{p-1}} \rangle \] is nilpotent for every \(g \in G\), \cite[Problem 10.59]{kourovka21}. We prove that if \(G\) is a periodic residually finite group admitting a splitting automorphism of prime order \(p\) then \(G\) is nilpotent of class bounded in terms of \(p\). This gives an affirmative answer, for residually finite groups, to the problem of Sozutov. We also prove that a possible counterexample to Sozutov's problem cannot be a Tarski monster.
format Preprint
id arxiv_https___arxiv_org_abs_2604_01011
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle A residually finite analogue of Kegel's theorem on splitting automorphisms
Di Bartolo, Alfonso
Ersoy, Kıvanç
Falcone, Giovanni
Group Theory
20E36 20F50 20F28 20D45
Thompson proved that every finite group admitting a fixed-point-free automorphism of prime order is nilpotent, and Kegel showed that the same conclusion holds for finite groups admitting a splitting automorphism of prime order. Motivated by these results, Sozutov asked whether a \(p'\)-group admitting a splitting automorphism of prime order is locally nilpotent if \[ \langle g, g^φ, \dots, g^{φ^{p-1}} \rangle \] is nilpotent for every \(g \in G\), \cite[Problem 10.59]{kourovka21}. We prove that if \(G\) is a periodic residually finite group admitting a splitting automorphism of prime order \(p\) then \(G\) is nilpotent of class bounded in terms of \(p\). This gives an affirmative answer, for residually finite groups, to the problem of Sozutov. We also prove that a possible counterexample to Sozutov's problem cannot be a Tarski monster.
title A residually finite analogue of Kegel's theorem on splitting automorphisms
topic Group Theory
20E36 20F50 20F28 20D45
url https://arxiv.org/abs/2604.01011