English
Related papers

Related papers: On minimal positive heights for blocks of almost q…

200 papers

Let $G$ be a finite group and let $p$ be a prime. In this paper, we prove a strengthened version of Brauer's height zero conjecture for the principal $p$-block of $G$ that takes the action of a certain group of Galois automorphisms into…

Representation Theory · Mathematics 2026-05-27 Alexander Moretó , Noelia Rizo , Gabriel A. L. Souza

We prove \emph{the other half} of Brauer's Height Zero Conjecture in the case of principal blocks.

Representation Theory · Mathematics 2021-02-17 Gunter Malle , Gabriel Navarro

In the representation theory of finite groups, there is a well-known and important conjecture due to M. Brou\'e. He conjectures that, for any prime p, if a p-block A of a finite group G has an abelian defect group P, then A and its Brauer…

Representation Theory · Mathematics 2015-03-17 Shigeo Koshitani , Jürgen Müller , Felix Noeske

We consider $p$-blocks with abelian defect groups and in the first part prove a relationship between its Loewy length and that for blocks of normal subgroups of index $p$. Using this, we show that if $B$ is a $2$-block of a finite group…

Representation Theory · Mathematics 2016-08-01 Charles W. Eaton , Michael Livesey

We study numerical invariants of 2-blocks with minimal nonabelian defect groups. These groups were classified by R\'edei. If the defect group is also metacyclic, then the block invariants are known. In the remaining cases there are only two…

Representation Theory · Mathematics 2010-12-09 Benjamin Sambale

In the representation theory of finite groups, Brou\'e's abelian defect group conjecture says that for any prime p if a p-block A of a finite group G has an abelian defect group P, then A and its Brauer corresponding block B of the…

Representation Theory · Mathematics 2013-09-30 Shigeo Koshitani , Jürgen Müller , Felix Noeske

We prove the Alperin-McKay Conjecture for all $p$-blocks of finite groups with metacyclic, minimal non-abelian defect groups. These are precisely the metacyclic groups whose derived subgroup have order $p$. In the special case $p=3$, we…

Representation Theory · Mathematics 2014-03-21 Benjamin Sambale

Several recent problems in the representation theory of finite groups require determining whether certain characters of almost simple groups belong to the principal block. Since the values of these characters are not yet known, we employ…

Representation Theory · Mathematics 2025-08-05 Richard Lyons , J. Miquel Martínez , Gabriel Navarro , Pham Huu Tiep

We give a reduction to quasisimple groups for Donovan's conjecture for blocks with abelian defect groups defined with respect to a suitable discrete valuation ring $\mathcal{O}$. Consequences are that Donovan's conjecture holds for…

Representation Theory · Mathematics 2019-05-27 Charles W. Eaton , Florian Eisele , Michael Livesey

We prove that if $B$ is a $p$-block with non-trivial defect group $D$ of a finite $p$-solvable group $G$, then $\ell(B) < p^r$, where $r$ is the sectional rank of $D$. We remark that there are infinitely many $p$-blocks $B$ with non-Abelian…

Representation Theory · Mathematics 2016-11-08 Gunter Malle , Geoffrey R. Robinson

We determine which quasi-simple groups have a non-principal $2$-block that is stable under complex conjugation. As a corollary, we determine that the Mathieu group $M_{22}$ is the only simple group not possessing a nontrivial irreducible…

Representation Theory · Mathematics 2026-05-25 John Revere McHugh , A. A. Schaeffer Fry

We determine the numerical invariants of blocks with defect group D_{2^n}\times C_{2^m}, where D_{2^n} denotes a dihedral group of order 2^n and C_{2^m} denotes a cyclic group of order 2^m. This generalizes Brauer's results for m=0. As a…

Representation Theory · Mathematics 2011-05-26 Benjamin Sambale

In a recent article, G. Malle and G. Navarro conjectured that the $p$-blocks of a finite group all of whose height 0 characters have the same degree are exactly the nilpotent blocks defined by M. Brou\'e and L. Puig. In this paper, we check…

Representation Theory · Mathematics 2011-05-03 Jean-Baptiste Gramain

Using the classification of finite simple groups we prove Alperin's weight conjecture and the character theoretic version of Broue's abelian defect group conjecture for 2-blocks of finite groups with an elementary abelian defect group of…

Representation Theory · Mathematics 2010-12-17 Radha Kessar , Shigeo Koshitani , Markus Linckelmann

In a recent paper, Gabriel Navarro and Pham Huu Tiep show that the so-called Alperin Weight Conjecture can be verified via the Classification of the Finite Simple Groups, provided any simple group fulfills a very precise list of conditions.…

Group Theory · Mathematics 2011-09-21 Lluis Puig

The Alperin-McKay conjecture is a longstanding open conjecture in the representation theory of finite groups. Sp\"ath showed that the Alperin-McKay conjecture holds if the so-called inductive Alperin-McKay (iAM) condition holds for all…

Representation Theory · Mathematics 2021-03-12 Lucas Ruhstorfer

As a sequel to [CS13b], we verify the so-called inductive AM-condition introduced in [Sp12] for simple groups of type A and blocks with maximal defect. This is part of the program set up to verify the Alperin-McKay conjecture through its…

Representation Theory · Mathematics 2014-03-20 Marc Cabanes , Britta Spaeth

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

We classify all $2$-blocks with abelian defect groups of rank $4$ up to Morita equivalence. The classification holds for blocks over a suitable discrete valuation ring as well as for those over an algebraically closed field. An application…

Group Theory · Mathematics 2024-09-16 Charles W. Eaton , Michael Livesey

The first author has recently classified the Morita equivalence classes of 2-blocks B of finite groups with elementary abelian defect group of order 32. In all but three cases he proved that the Morita equivalence class determines the…

Representation Theory · Mathematics 2020-11-16 Cesare G. Ardito , Benjamin Sambale