On the intersection of principal blocks

Gabriel Navarro, A. A. Schaeffer Fry and Pham Huu Tiep

Vol. 336 (2025), No. 1-2, 399–413

DOI: 10.2140/pjm.2025.336.399

Abstract

If $p$ and $q$ are two primes, $G$ is a finite group, and $B_p(G)$ is the set of complex irreducible characters in the principal $p$-block of $G$, we study $|B_p(G)\cap B_q(G)|$ and its possible relation with some local subgroup.

To the memory of Gary Seitz

Keywords

modular representations, Brauer blocks, Sylow subgroups

Mathematical Subject Classification

Primary: 20C20

Secondary: 20C15, 20C33, 20C34, 20D20

Milestones

Received: 5 April 2024

Revised: 12 August 2024

Accepted: 19 August 2024

Published: 26 May 2025