English

Overgroups of regular unipotent elements in reductive groups

Group Theory 2023-06-22 v3

Abstract

We study reductive subgroups HH of a reductive linear algebraic group GG -- possibly non-connected -- such that HH contains a regular unipotent element of GG. We show that under suitable hypotheses, such subgroups are GG-irreducible in the sense of Serre. This generalizes results of Malle, Testerman and Zalesski. We obtain analogous results for Lie algebras and for finite groups of Lie type. Our proofs are short, conceptual and uniform.

Keywords

Cite

@article{arxiv.2107.01925,
  title  = {Overgroups of regular unipotent elements in reductive groups},
  author = {Michael Bate and Ben Martin and Gerhard Roehrle},
  journal= {arXiv preprint arXiv:2107.01925},
  year   = {2023}
}

Comments

13 pages; v2 added Corollary 5.2; v3 final version; some references added, further small changes; to appear in Forum of Mathematics, Sigma

R2 v1 2026-06-24T03:53:39.105Z