Real 2-blocks in quasi-simple groups
Representation Theory
2026-05-25 v1 Group Theory
Abstract
We determine which quasi-simple groups have a non-principal -block that is stable under complex conjugation. As a corollary, we determine that the Mathieu group is the only simple group not possessing a nontrivial irreducible Brauer character of quadratic type, answering a recent question of Gow and Murray.
Keywords
Cite
@article{arxiv.2605.22969,
title = {Real 2-blocks in quasi-simple groups},
author = {John Revere McHugh and A. A. Schaeffer Fry},
journal= {arXiv preprint arXiv:2605.22969},
year = {2026}
}