English

Fixed point conditions for non-coprime actions

Group Theory 2025-04-30 v1

Abstract

In the setting of finite groups, suppose JJ acts on NN via automorphisms so that the induced semidirect product NJN\rtimes J acts on some non-empty set Ω\Omega, with NN acting transitively. Glauberman proved that if the orders of JJ and NN are coprime, then JJ fixes a point in Ω\Omega. We consider the non-coprime case and show that if NN is abelian and a Sylow pp-subgroup of JJ fixes a point in Ω\Omega for each prime pp, then JJ fixes a point in Ω\Omega. We also show that if NN is nilpotent, NJN\rtimes J is supersoluble, and a Sylow pp-subgroup of JJ fixes a point in Ω\Omega for each prime pp, then JJ fixes a point in Ω\Omega.

Keywords

Cite

@article{arxiv.2308.12286,
  title  = {Fixed point conditions for non-coprime actions},
  author = {Michael C. Burkhart},
  journal= {arXiv preprint arXiv:2308.12286},
  year   = {2025}
}
R2 v1 2026-06-28T12:02:44.231Z