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arXiv · 2505.03017

Local--global generation property of commutators in finite $π$-soluble groups

Cristina Acciarri·Robert M. Guralnick·Evgeny Khukhro·Pavel Shumyatsky
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Abstract

For a group $A$ acting by automorphisms on a group $G$, let $I_G(A)$ denote the set of commutators $[g,a]=g^{-1}g^a$, where $g\in G$ and $a\in A$, so that $[G,A]$ is the subgroup generated by $I_G(A)$. We prove that if $A$ is a $π$-group of automorphisms of a $π$-soluble finite group $G$ such that any subset of $I_G(A)$ generates a subgroup that can be generated by $r$ elements, then the rank of $[G,A]$ is bounded in terms of $r$. Examples show that such a result does not hold without the assumption of $π$-solubility. Earlier we obtained this type of results for groups of coprime automorphisms and for Sylow $p$-subgroups of $p$-soluble groups.

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Cristina Acciarri, Robert M. Guralnick, Evgeny Khukhro, Pavel Shumyatsky. 2026-05-17. Local--global generation property of commutators in finite $π$-soluble groups. https://arxiv.org/abs/2505.03017

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