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Related papers: Character triples and Shoda pairs

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In this paper we give an explicit description of primitive central idempotents of rational group algebras of finite abelian groups using long presentation, and determine their Wedderburn decompositions.

Representation Theory · Mathematics 2015-09-09 Ravi S. Kulkarni , Soham S. Pradhan

We present a method to explicitly compute a complete set of orthogonal primitive idempotents in a simple component with Schur index 1 of a rational group algebra $\mathbb{Q}G$ for $G$ a finite generalized strongly monomial group. For the…

Rings and Algebras · Mathematics 2024-01-17 Gurmeet K. Bakshi , Jyoti Garg , Gabriela Olteanu

We construct a supercharacter theory for the group of invertible elements of a reduced algebra. For the case of the triangular group, we obtain the formula for values of supercharacters on superclasses.

Representation Theory · Mathematics 2015-06-10 A. N. Panov

The character theory of finite groups has numerous basic questions that are often already quite involved: enumerating of irreducible characters, their character formulas, point-wise product decompositions, and restriction/induction between…

Representation Theory · Mathematics 2018-10-03 Farid Aliniaeifard , Nathaniel Thiem

In this paper, we prove Sp\"ath's Character Triple Conjecture for $p$-solvable groups. This is a conjecture proposed by Sp\"ath during the reduction process of Dade's Projective Conjecture to quasisimple groups. In addition, as suggested by…

Representation Theory · Mathematics 2021-11-04 Damiano Rossi

In this article we formulate and prove the main theorems of the theory of character sheaves on unipotent groups over an algebraically closed field of characteristic p>0. In particular, we show that every admissible pair for such a group G…

Representation Theory · Mathematics 2013-01-08 Mitya Boyarchenko , Vladimir Drinfeld

We introduce Morita and Rickard equivalences over a group graded G-algebra between block extensions. A consequence of such equivalences is that Sp\"ath's central order relation holds between two corresponding character triples.

Representation Theory · Mathematics 2019-12-13 Andrei Marcus , Virgilius-Aurelian Minuta

In this work, the automorphism group schemes of finite-dimensional simple Jordan pairs of types I and IV, and of some Jordan triple systems related to them, are determined. We assume $\mathrm{char}(\mathbb{F}) \neq 2$ for the base field…

Rings and Algebras · Mathematics 2025-04-23 Diego Aranda-Orna , Alberto Daza-García

An approach to representations of finite groups is presented without recourse to character theory. Considering the group algebra C[G] as an algebra of linear maps on C[G] (by left multiplication), we derive the primitive central idempotents…

Representation Theory · Mathematics 2008-03-31 Robin Endelman , Manash Mukherjee

The Brauer algebra has a basis of diagrams and these generate a monoid $H$ consisting of scalar multiples of diagrams. Following a recent paper by Kudryavtseva and Mazorchuk, we define and completely determine three types of conjugation in…

Representation Theory · Mathematics 2009-11-30 Armin Shalile

In this investigation of character tables of finite groups we study basic sets and associated representation theoretic data for complementary sets of conjugacy classes. For the symmetric groups we find unexpected properties of characters on…

Representation Theory · Mathematics 2012-06-05 Christine Bessenrodt , Jørn B. Olsson

Creation operators are given for the three distinguished bases of the type BCD universal character ring of Koike and Terada yielding an elegant way of treating computations for all three types in a unified manner. Deformed versions of these…

Combinatorics · Mathematics 2007-05-23 Mark Shimozono , Mike Zabrocki

We construct algebraic surfaces with a large number of type A singularities. Bivariate polynomials presented in previous works for the construction of nodal surfaces and certain families of Belyi polynomials are used. In some cases explicit…

Algebraic Geometry · Mathematics 2025-10-17 Juan García Escudero

We describe a basis of the centre of the Schur algebra which comes from conjugacy classes in the symmetric group via Schur-Weyl duality. We give a combinatorial description of expansions of these basis elements in terms of the basis…

Representation Theory · Mathematics 2016-02-25 T. Geetha , Amritanshu Prasad

Amdeberhan recently proposed certain equalities between sums in the character table of symmetric groups. These equalities are between signed column sums in the character table, summing over the rows labeled by partitions in $\Ev$, where…

Combinatorics · Mathematics 2025-09-24 David J. Hemmer , Armin Straub , Karlee Westrem

Let $G(q)$ be a Chevalley group over a finite field $F_q$. By Lusztig's and Shoji's work, the problem of computing the values of the unipotent characters of $G(q)$ is solved, in principle, by the theory of character sheaves; one issue in…

Representation Theory · Mathematics 2017-11-27 Meinolf Geck

This paper contains the results collected so far on polynomial composites in terms of many basic algebraic properties. Since it is a polynomial structure, results for monoid domains come in here and there. The second part of the paper…

Commutative Algebra · Mathematics 2021-06-01 Magdalena Jankowska , Lukasz Matysiak

In this paper, we extend the notion of Shintani descent to general (possibly disconnected) algebraic groups defined over a finite field $\mathbb{F}_q$. For this, it is essential to treat all the pure inner $\mathbb{F}_q$-rational forms of…

Representation Theory · Mathematics 2019-02-20 Tanmay Deshpande

We compute the rank of the group of central units in the integral group ring $\Z G$ of a finite strongly monomial group $G$. The formula obtained is in terms of the strong Shoda pairs of $G$. Next we construct a virtual basis of the group…

Rings and Algebras · Mathematics 2013-04-25 Eric Jespers , Gabriela Olteanu , Ángel del Río , Inneke Van Gelder

We show how the character tables of the groups $E_6(q)_{\text{ad}}$ and ${^2\!E}_6(q)_{\text{ad}}$ can be constructed, where $q$ is a power of~$2$. (Partial results are also obtained for any $q$ not divisible by~$3$.) This is based on…

Representation Theory · Mathematics 2024-05-15 Meinolf Geck