English
Related papers

Related papers: On blocks with trivial source simple modules

200 papers

We investigate simple endotrivial modules of finite quasi-simple groups and classify them in several important cases. This is motivated by a recent result of Robinson showing that simple endotrivial modules of most groups come from…

Group Theory · Mathematics 2013-09-25 Caroline Lassueur , Gunter Malle , Elisabeth Schulte

We establish a genericity property in the representation theory of a flat family of finite-dimensional algebras in the sense of Cline-Parshal-Scott. More precisely, we show that the decomposition matrices as introduced by Geck and Rouquier…

Representation Theory · Mathematics 2016-04-13 Ulrich Thiel

For any grading by an abelian group $G$ on the exceptional simple Lie algebra $\mathcal{L}$ of type $E_6$ or $E_7$ over an algebraically closed field of characteristic zero, we compute the graded Brauer invariants of simple…

Representation Theory · Mathematics 2017-11-27 Cristina Draper , Alberto Elduque , Mikhail Kochetov

Let $\mathcal B(\delta)$ be the Brauer category over the complex field $\mathbb C$ with the parameter $\delta$. In non-semisimple case, $\delta$ is an integer, and each weight space of $(\frac{\delta}2-1)$th semi-infinite wedge space…

Representation Theory · Mathematics 2023-07-18 Mengmeng Gao , Hebing Rui , Linliang Song

Using a stable equivalence due to Rouquier, we prove that Broue's abelian defect group conjecture holds for 3-blocks of defect 2 whose Brauer correspondent has a unique isomorphism class of simple modules. The proof makes use of the fact,…

Group Theory · Mathematics 2014-02-26 Radha Kessar

Let B be a p-block of a finite group G with abelian defect group D such that S\unlhd G, S'=S, G/Z(S)\le\Aut(S) and S/Z(S) is a sporadic simple group. We show that B is isotypic to its Brauer correspondent in N_G(D) in the sense of Brou\'e.…

Representation Theory · Mathematics 2015-09-01 Benjamin Sambale

The aim of this paper is to apply character properties of Frobenius group to a local block form of an group algebra. We start by establishing a block form of Brauer permutation Lemma by using block participation of conjugate classes of a…

Group Theory · Mathematics 2020-10-30 Jiwen Zeng , Jiping Zhang

There are similarities between algebraic Lie theory and a geometric description of the blocks of the Brauer algebra in characteristic zero. Motivated by this, we study the alcove geometry of a certain reflection group action. We provide…

Representation Theory · Mathematics 2008-07-25 Anton Cox , Maud De Visscher , Paul Martin

This paper introduces the notion of Brauer-friendly modules, a generalisation of endo-p-permutation modules. A module over a block algebra OGe is said to be Brauer-friendly if it is a direct sum of indecomposable modules with compatible…

Representation Theory · Mathematics 2013-07-16 Erwan Biland

We present three examples of Green biset functors for which their simple modules can be parametrized. These are particular cases of a conjecture by Serge Bouc classifying the simple modules over a Green biset functor A, that generalizes the…

Representation Theory · Mathematics 2012-06-26 Nadia Romero

In this paper, we construct the permutation modules and Young modules for Brauer algebras of type $C$ by extending the representation theory of the group algebra of hyperoctahedral groups. Additionally, we develop a stratifying system for…

Representation Theory · Mathematics 2025-07-21 Sulakhana Chowdhury , Geetha Thangavelu

Let $(A,\sigma)$ be a central simple algebra with an orthogonal involution. It is well-known that $O(A,\sigma)$ contains elements of reduced norm $-1$ if and only if the Brauer class of $A$ is trivial. We generalize this statement to…

Algebraic Geometry · Mathematics 2020-07-06 Uriya A. First

In this paper, we study Azumaya algebras and Brauer groups in derived algebraic geometry. We establish various fundamental facts about Brauer groups in this setting, and we provide a computational tool, which we use to compute the Brauer…

Algebraic Geometry · Mathematics 2014-11-11 Benjamin Antieau , David Gepner

This series of papers is a contribution to the program of classifying $p$-blocks of finite groups up to source algebra equivalence, starting with the case of cyclic blocks. To any $p$-block $\mathbf{B}$ of a finite group with cyclic defect…

Representation Theory · Mathematics 2026-01-06 Gerhard Hiss , Caroline Lassueur

Let G be a simple classical algebraic group over an algebraically closed field of positive characteristic. We describe the support variety of a simple G-module over the r-th Frobenius kernel of G, in terms of its calculation over the first…

Representation Theory · Mathematics 2012-09-27 Paul Sobaje

In this paper we consider the Brauer groups of algebraic stacks and GIT quotients: the only algebraic stacks we consider in this paper are quotient stacks [X/G], where X is a smooth scheme of finite type over a field k, and G is a linear…

Algebraic Geometry · Mathematics 2021-06-29 Jaya Iyer , Roy Joshua

In this paper, we construct, investigate and, in some cases, classify several new classes of (simple) modules over the Takiff $\mathfrak{sl}_{2}$. More precisely, we first explicitly construct and classify, up to isomorphism, all modules…

Representation Theory · Mathematics 2022-11-15 Xiaoyu Zhu

This article undertakes an exploration of simple modules of 3-cyclic quantum Weyl algebra at roots of unity. Under the roots of unity assumption, the algebra becomes a Polynomial Identity algebra and the vector space dimension of the simple…

Representation Theory · Mathematics 2024-06-21 Sanu Bera , Sugata Mandal , Snehashis Mukherjee , Soumendu Nandy

We study the periplectic Brauer algebra introduced by Moon in the study of invariant theory for periplectic Lie superalgebras. We determine when the algebra is quasi-hereditary and, for fields of characteristic zero, describe the block…

Representation Theory · Mathematics 2018-11-27 Kevin Coulembier

Let A be an Azumaya algebra over a smooth projective variety X or more generally, a torsion free coherent sheaf of algebras over X whose generic fiber is a central simple algebra. We show that generically simple torsion free A-module…

Algebraic Geometry · Mathematics 2007-05-23 Norbert Hoffmann , Ulrich Stuhler