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Related papers: 2-Blocks with minimal nonabelian defect groups

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This article focuses on the study of zero-sum invariants of finite non-abelian groups. We address two main problems: the first centers on the ordered Davenport constant and the second on Gao's constant. We establish a connection between the…

Combinatorics · Mathematics 2026-01-06 Naveen K. Godara , Renu Joshi , Eshita Mazumdar

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 prove Brauer's k(B)-Conjecture for the 3-blocks with abelian defect groups of rank at most 5 and for all 3-blocks of defect at most 4. For this purpose we develop a computer algorithm to construct isotypies based on a method of Usami and…

Representation Theory · Mathematics 2019-11-26 Cesare G. Ardito , Benjamin Sambale

The inductive blockwise Alperin weight condition is a system of conditions whose verification for all non-abelian finite simple groups would imply the blockwise Alperin weight conjecture. We establish this condition for the groups $G_2(q)$,…

Representation Theory · Mathematics 2016-03-17 Elisabeth Schulte

We study blocks with an abelian defect group and a cyclic inertial quotient acting freely but not transitively. We prove that when p=2, such blocks are inertial, i.e. basic Morita equivalent to their Brauer correspondent. Together with a…

Representation Theory · Mathematics 2020-10-20 Cesare Giulio Ardito , Elliot McKernon

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

This paper has two main parts. Firstly, we give a classification of the $\ell$-blocks of finite special linear and unitary groups $SL_n(\epsilon q)$ in the non-defining characteristic $\ell\ge 3$. Secondly, we describe how the…

Representation Theory · Mathematics 2019-01-18 Zhicheng Feng

We verify the inductive blockwise Alperin weight (BAW) and the inductive Alperin-McKay (AM) conditions introduced by the second author for blocks of finite quasisimple groups with cyclic defect groups. Furthermore we establish a criterion…

Group Theory · Mathematics 2013-10-22 Shigeo Koshitani , Britta Spaeth

Let $k$ be an algebraically closed field of characteristic $p$, and let $\mathcal{O}$ be either $k$ or its ring of Witt vectors $W(k)$. Let $G$ a finite group and $B$ a block of $\mathcal{O}G$ with normal abelian defect group and abelian…

Representation Theory · Mathematics 2018-08-23 David Benson , Radha Kessar , Markus Linckelmann

In this paper characters of the normaliser of $d$-split Levi subgroups in $\mathrm {SL}_n(q)$ and $\mathrm {SU}_n(q)$ are parametrized with a particular focus on the Clifford theory between the Levi subgroup and its normalizer.These results…

Representation Theory · Mathematics 2019-01-16 Julian Brough , Britta Späth

The Malle-Navarro conjecture relates central block theoretic invariants in two inequalities. In this paper, we prove the conjecture for the 2-blocks and the unipotent 3-blocks of the general linear and unitary groups in non-defining…

Representation Theory · Mathematics 2019-12-23 Sofia Brenner

Let G be a 2-group of order 2^n, n>5, and nilpotency class n-2. The invariants of such groups determined by their group algebras over the field of two elements are given in the paper.

Group Theory · Mathematics 2007-05-23 Czeslaw Baginski , Alexander Konovalov

This paper has two main results. Firstly, we complete the parametrisation of all p-blocks of finite quasi-simple groups by finding the so-called quasi-isolated blocks of exceptional groups of Lie type for bad primes. This relies on the…

Group Theory · Mathematics 2022-03-08 Radha Kessar , Gunter Malle

We extend a theorem of Kessar and Linckelmann concerning Morita equivalences and Brauer character bijections between blocks to virtual Morita equivalences. As a corollary, we obtain that Navarro's refinement of Alperin's weight conjecture…

Representation Theory · Mathematics 2024-03-27 Xin Huang

We study Brauer's long-standing $k(B)$-conjecture on the number of characters in $p$-blocks for finite quasi-simple groups and show that their blocks do not occur as a minimal counterexample for $p\ge5$ nor in the case of abelian defect.…

Representation Theory · Mathematics 2018-04-03 Gunter Malle

Recently, a new conjecture on the degrees of the irreducible Brauer characters of a finite group was presented by the second author. In this paper we propose a 'local' version of this conjecture for blocks B of finite groups, giving a lower…

Group Theory · Mathematics 2007-05-23 Thorsten Holm , Wolfgang Willems

We establish the inductive blockwise Alperin weight condition for simple groups of Lie type $\mathsf C$ and the bad prime $2$. As a main step, we derive a labelling set for the irreducible $2$-Brauer characters of the finite symplectic…

Representation Theory · Mathematics 2020-07-28 Zhicheng Feng , Gunter Malle

In this paper, we calculate the numbers of irreducible ordinary characters and irreducible Brauer characters in a block of a finite group $G$, whose associated fusion system over a 2-subgroup $P$ of $G$ (which is a defect group of the…

Group Theory · Mathematics 2018-08-30 Xueqin Hu , Yuanyang Zhou

The longstanding Alperin weight conjecture and its blockwise version have been reduced to simple groups recently by Navarro, Tiep, Spaeth and Koshitani. Thus, to prove this conjecture, it suffices to verify the corresponding inductive…

Representation Theory · Mathematics 2019-01-23 Conghui Li

We study a weakened version of the Holm--Willems Local Conjecture. The problem is reduced to quasi-simple groups under the assumption that the defect group is abelian. Complete proofs are provided in the case \(p = 2\).

Group Theory · Mathematics 2026-04-14 Hanxiao Li , Kun Zhang