activity
20232026
collaborators

10 papers

math.RT2026

On -blocks with quaternion defect groups

Charles Eaton, Florian Eisele, Radha Kessar +2

We determine the Morita equivalence classes of -blocks with quaternion defect groups of arbitrary -power order, thereby completing the proof of Donovan's conjecture for block…

math.RT2026

Galois automorphisms and blocks covering unipotent blocks

L. Ruhstorfer, A. A. Schaeffer Fry

In this paper we prove that a recent condition of Lyons--Martínez--Navarro--Tiep, regarding the field of values of extensions of characters in principal blocks, is satisfied for al…

math.GR2026

Galois action on the principal block and generation of Sylow 3-subgroups

Eden Ketchum, J. Miquel Martínez, Noelia Rizo +1

In this paper, we prove one direction of a conjecture of Navarro-Rizo-Schaeffer Fry-Vallejo positing an algorithm to determine from the character table whether a finite group has $…

math.GR2025

Sylow subgroups and the number of irreducible characters of degrees divisible by a prime

James P. Cossey, Mark L. Lewis, A. A. Schaeffer Fry +1

Let be a finite group and a prime. We establish an upper bound for the derived length of a Sylow -subgroup of in terms of the number of irreducible characters of …

math.RT2025

The Picky Conjecture for groups of Lie type

Gunter Malle, A. A. Schaeffer Fry

Recently, Moretó and Rizo proposed a conjecture, known as the Picky Conjecture, proposing new character correspondences extending the McKay Conjecture. We prove the Picky Conjectur…

math.RT2025

The Isaacs--Navarro Galois conjecture

L. Ruhstorfer, A. A. Schaeffer Fry

We prove the original Galois refinement of the McKay conjecture, proposed by Isaacs--Navarro in 2002, providing an important subcase of the celebrated McKay--Navarro conjecture wit…

math.GR2024

The -rationality of height-zero characters

Nguyen N. Hung, A. A. Schaeffer Fry

We propose and present evidence for a conjectural global-local phenomenon concerning the -rationality of -height-zero characters. Specifically, if is a height-zero charac…

math.RT2024

On minimal positive heights for blocks of almost quasi-simple groups

Gunter Malle, A. A. Schaeffer Fry

The Eaton--Moretó conjecture extends the recently-proven Brauer height zero conjecture to blocks with non-abelian defect group, positing equality between the minimal positive heigh…

math.RT2024

A Brauer--Galois height zero conjecture

Gunter Malle, Alexander Moretó, Noelia Rizo +1

Recently, Malle and Navarro obtained a Galois strengthening of Brauer's height zero conjecture for principal -blocks when , considering a particular Galois automorphism of…

math.GR2023

Brauer's problem 21 for principal blocks

Alexander Moretó, Noelia Rizo, A. A. Schaeffer Fry

Problem 21 of Brauer's list of problems from 1963 asks whether for any positive integer k there are finitely many isomorphism classes of groups that occur as the defect group of a…