English
Related papers

Related papers: The McKay Conjecture on character degrees

200 papers

This paper proposes a conjectural framework for Alperin's Main Problem of Block Theory from 1976. The character sets considered here are defined by nonvanishing at given elements, not only by degree conditions. From this point of view,…

Representation Theory · Mathematics 2026-05-22 Alexander Moretó

This paper is a contribution to the general program introduced by Isaacs, Malle and Navarro to prove the McKay conjecture in the representation theory of finite groups. We develop new methods for dealing with simple groups of Lie type in…

Representation Theory · Mathematics 2009-11-18 Olivier Brunat , Frank Himstedt

We determine the non-abelian composition factors of the finite groups with Sylow normalizers of odd order. As a consequence, among others, we prove the McKay conjecture and the Alperin weight conjecture for these groups.

Group Theory · Mathematics 2016-02-25 Robert M. Guralnick , Gabriel Navarro , Pham Huu Tiep

We prove that if the average of the degrees of the irreducible characters of a finite group $G$ is less than 16/5, then $G$ is solvable. This solves a conjecture of I.M. Isaacs, M. Loukaki, and the first author. We discuss related…

Group Theory · Mathematics 2013-12-06 Alexander Moretó , Hung Ngoc Nguyen

In this paper we verify Navarro's refinement of the McKay conjecture for quasi-simple groups of Lie type in their defining characteristic. Navarro's refinement takes into account the action of specific Galois automorphisms on the characters…

Representation Theory · Mathematics 2020-11-02 Lucas Ruhstorfer

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 $2$-generated Sylow $3$-subgroups. This gives further…

Group Theory · Mathematics 2026-02-17 Eden Ketchum , J. Miquel Martínez , Noelia Rizo , A. A. Schaeffer Fry

We propose a new refinement of the McKay conjecture and we prove it for symmetric groups.

Representation Theory · Mathematics 2026-05-15 Eugenio Giannelli

A new type of conjectures on characters of finite groups, related to the McKay conjecture, have recently been proposed. In this paper, we study these conjectures for symmetric groups.

Group Theory · Mathematics 2026-02-11 Juan Martínez Madrid

In 2005 Wolfgang Willems put forward a conjecture proposing a lower bound for the sum of squares of the degrees of the irreducible $p$-Brauer characters of a finite group $G$. We prove this conjecture for the prime $p=2$. For this we rely…

Representation Theory · Mathematics 2020-12-17 Gunter Malle

Diaconis and Isaacs define a supercharacter theory for algebra groups over a finite field by constructing certain unions of conjugacy classes called superclasses and certain reducible characters called supercharacters. This work…

Representation Theory · Mathematics 2011-03-29 Eric Marberg

Let $G$ be a finite group and $cd(G)$ denote the set of complex irreducible character degrees of $G$. In this paper, we prove that if $G$ is a finite group and $H$ is an almost simple group whose socle is Mathieu group such that $cd(G)…

Group Theory · Mathematics 2016-01-26 Seyed Hassan Alavi , Ashraf Daneshkhah , Ali Jafari

Let $p$ be a prime and $G$ a finite group. We propose a strong bound for the number of $p'$-degree irreducible characters of $G$ in terms of the commutator factor group of a Sylow $p$-subgroup of $G$. The bound arises from a recent…

Representation Theory · Mathematics 2023-02-16 Nguyen N. Hung

We refine the reduction theorem of the McKay Conjecture proved by Isaacs, Malle and Navarro. Assuming the inductive McKay condition, we obtain a strong version of the McKay Conjecture that gives central isomorphic character triples.

Representation Theory · Mathematics 2022-04-22 Damiano Rossi

The so-called inductive McKay condition on finite simple groups, due to Isaacs-Malle-Navarro (2007), has been recently reformulated by Sp\"ath. We show that this reformulation applies to the reduction theorem for Alperin's weight…

Representation Theory · Mathematics 2014-02-26 Marc Cabanes

We prove that the number of irreducible ordinary characters in the principal $p$-block of a finite group $G$ of order divisible by $p$ is always at least $2\sqrt{p-1}$. This confirms a conjecture of H\'{e}thelyi and K\"{u}lshammer for…

Representation Theory · Mathematics 2023-05-31 Nguyen Ngoc Hung , A. A. Schaeffer Fry

We prove that the order of a finite group $G$ with trivial solvable radical is bounded above in terms of ${\rm acd}(G)$, the average degree of the irreducible characters. It is not true that the index of the Fitting subgroup is bounded…

Group Theory · Mathematics 2022-10-04 Alexander Moretó

A new conjecture on characters of finite groups, related to the McKay conjecture, was proposed recently by the first and third authors. In this paper, we prove it for $p$-solvable groups when $p$ is odd.

Representation Theory · Mathematics 2025-06-16 Alexander Moretó , Gabriel Navarro , Noelia Rizo

In 1973, I. M. Isaacs described a correspondence between characters of degree not divisible by a fixed prime $p$ of a finite solvable group $G$ and those of the normalizer of Sylow $p$-subgroup of $G$, whenever the index of the normalizer…

Representation Theory · Mathematics 2019-09-10 Carolina Vallejo

Given an almost simple group $A$, we algorithmically show that the character table of $A$ determines whether or not the Sylow 3-subgroups of $A$ are 2-generated. We show this property is equivalent to a condition involving the Galois action…

Group Theory · Mathematics 2026-04-24 Eden Ketchum

A classical theorem on character degrees states that if a finite group has fewer than four character degrees, then the group is solvable. We prove a corresponding result on character values by showing that if a finite group has fewer than…

Group Theory · Mathematics 2021-06-30 Sesuai Y. Madanha