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Let $k$ be a field of odd prime characteristic $p$. We calculate the Lie algebra structure of the first Hochschild cohomology of a class of quantum complete intersections over $k$. As a consequence, we prove that if $B$ is a defect…

Representation Theory · Mathematics 2016-04-18 David John Benson , Radha Kessar , Markus Linckelmann

We demonstrate that the blocks of a profinite group whose defect groups are cyclic have a Brauer tree algebra structure analogous to the case of finite groups. We show further that the Brauer tree of a block with defect group…

Group Theory · Mathematics 2022-02-23 Ricardo J. Franquiz Flores , John W. MacQuarrie

Necessary and sufficient conditions are given for a $G$-graded simple module over a unital associative algebra, graded by an abelian group $G$, to be isomorphic to a loop module of a simple module, as well as for two such loop modules to be…

Representation Theory · Mathematics 2016-09-12 Alberto Elduque , Mikhail Kochetov

We study the weight modules over affine Kac-Moody algebras from the view point of vertex algebras, and determine the abelian category of weight modules for the simple affine vertex algebra $L_k(\mathfrak{sl}_2)$ at any non-integral…

Representation Theory · Mathematics 2023-11-20 Tomoyuki Arakawa , Thomas Creutzig , Kazuya Kawasetsu

Let ${\mathcal W}_n$ be the Lie algebra of polynomial vector fields. We classify simple weight ${\mathcal W}_n$-modules $M$ with finite weight multiplicities. We prove that every such nontrivial module $M$ is either a tensor module or the…

Representation Theory · Mathematics 2021-02-19 Dimitar Grantcharov , Vera Serganova

The cohomology of the degree-$n$ general linear group over a finite field of characteristic $p$, with coefficients also in characteristic $p$, remains poorly understood. For example, the lowest degree previously known to contain nontrivial…

Algebraic Topology · Mathematics 2017-11-08 Anssi Lahtinen , David Sprehn

In this paper, we examine the relation between certain subclasses of the classes of Gorenstein projective, Gorenstein flat and Gorenstein injective modules over a group algebra, which consist of the cofibrant, cofibrant-flat and fibrant…

K-Theory and Homology · Mathematics 2025-03-10 Ioannis Emmanouil , Wei Ren

Let G be a finite group. The Plesken Lie algebra L[G] is a subalgebra of the complex group algebra C[G] and admits a direct-sum decomposition into simple Lie algebras based on the ordinary character theory of G. In this paper we review the…

Representation Theory · Mathematics 2024-06-21 John Cullinan

We obtain a classification of metaplectic modular categories: every metaplectic modular category is a gauging of the particle-hole symmetry of a cyclic modular category. Our classification suggests a conjecture that every weakly-integral…

Quantum Algebra · Mathematics 2017-03-13 Eddy Ardonne , Meng Cheng , Eric C. Rowell , Zhenghan Wang

The main objective of this project is to determine all irreducible modules of a given modular Lie algebra. In contrast to ordinary Lie algebras, modular Lie algebras require an additional structure known as the p-mapping. The minimal…

Rings and Algebras · Mathematics 2025-11-05 Eun H. Park

A parabolic subalgebra $\mathfrak{p}$ of a complex semisimple Lie algebra $\mathfrak{g}$ is called a parabolic subalgebra of abelian type if its nilpotent radical is abelian. In this paper, we provide a complete characterization of the…

Representation Theory · Mathematics 2016-03-22 Haian He

Let $K$ be a differential field over $\C$ with derivation $D$, $G$ a finite linear automorphism group over $K$ which preserves $D$, and $K^G$ the fixed point subfield of $K$ under the action of $G$. We show that every finite-dimensional…

Quantum Algebra · Mathematics 2013-12-18 Kenichiro Tanabe

Many common finite p-groups admit automorphisms of order coprime to p, and when p is odd, it is reasonably difficult to find finite p-groups whose automorphism group is a p-group. Yet the goal of this paper is to prove that the automorphism…

Group Theory · Mathematics 2013-05-09 Geir T. Helleloid , Ursula Martin

We classify the Morita equivalence classes of principal blocks with elementary abelian defect groups of order 64 with respect to a complete discrete valuation ring with an algebraically closed residue field of characteristic two.

Representation Theory · Mathematics 2020-10-16 Cesare Giulio Ardito

The objective of this research paper is to study the relationship between a block of a finite group and a defect group of such block. We define a new notion which is called a strongly $k(D)$-block and give a necessary and sufficient…

Representation Theory · Mathematics 2014-09-25 Ahmad Alghamdi

For simple twisted group algebra over a group $G$, if $G^{\shortmid}$ is Hall subgroup of $G$ then the semi-center is simple. Simple twisted groups algebras correspond to groups of central type. We classify all groups of central type of…

Rings and Algebras · Mathematics 2016-01-26 Ofir Schnabel

We introduce the $N=2$ Lie conformal superalgebras ${\frak {K}}(p)$ of Block type, and classify their finite irreducible conformal modules for any nonzero parameter $p$. where $p$ is a nonzero complex number. In particular, we show that…

Representation Theory · Mathematics 2020-05-13 Chunguang Xia

Soit F un corps local non archimedien de caracteristique residuelle p. On designe par R un corps algebriquement clos de caracteristique p et par Q une cloture algebrique du corps des nombres p-adiques. On classifie les modules simples de…

Representation Theory · Mathematics 2007-05-23 Rachel Ollivier

We prove that if $b$ is a block of a finite group with normal abelian defect group and inertial quotient a direct product of elementary abelian groups, then $\operatorname{Picent}(b)$ is trivial. We also provide examples of blocks $b$ of…

Representation Theory · Mathematics 2020-02-26 Michael Livesey , Claudio Marchi

The submodule structure of general Specht modules in prime characteristic is a difficult open problem. Kleshchev and Sheth [Journal of Algebra, 221(2), pp.705-722] gave a combinatorial description of the submodule structure of Specht…

Representation Theory · Mathematics 2024-05-10 Zain Ahmed Kapadia