English
Related papers

Related papers: Restricting unipotent characters in special orthog…

200 papers

For an irreducible character $\chi$ of a finite group $G$, its kernel is defined as $\text{ker }\chi=\{g\in G: \chi(g)=\chi(1)\}$. In this paper we characterize the finite groups of prime power order(for odd prime) in which kernels of all…

Group Theory · Mathematics 2025-12-23 Nabajit Talukdar

The method of little groups describes the irreducible characters of semidirect products with abelian normal subgroups in terms of the irreducible characters of the factor groups. We modify this method to construct supercharacter theories of…

Representation Theory · Mathematics 2016-04-28 Scott Andrews

In this article, we determine all inequivalent irreducible rational matrix representations of groups of order $p^5$, where $p$ is an odd prime. We also derive combinatorial formulations for the Wedderburn decomposition of rational group…

Representation Theory · Mathematics 2025-04-02 Ram Karan Choudhary , Sunil Kumar Prajapati

In this paper, we consider the construction of irreducible representations of finite pattern groups in terms of Panov's associative polarization, which is a finite-field analogue of Kirillov's orbital method. Using this construction, first,…

Representation Theory · Mathematics 2026-01-19 Chufeng Nien , Chenyan Wu

For p odd, the Lie group SO_0(p+1,p+1) has a family of unitary degenerate principal series representations realized on the space of real (p+1) by (p+1) skew symmetric matrices, similar to the Stein's complementary series for SL(2n,C) or…

Representation Theory · Mathematics 2012-06-15 Veronique Fischer , Genkai Zhang

This text brings to an end the classification of non-reduced parabolic subgroups in positive characteristic, especially two and three: they are all obtained as intersections of parabolics having maximal reduced part. We prove this result…

Algebraic Geometry · Mathematics 2023-12-04 Matilde Maccan

We give a complete list of indecomposable characters of the infinite symmetric semigroup. In comparison with the analogous list for the infinite symmetric group, one should introduce only one new parameter, which has a clear combinatorial…

Representation Theory · Mathematics 2011-02-23 Anatoly Vershik , Pavel Nikitin

Given a finite-dimensional faithful representation $V$ of a linearly reductive group $G$ over a field $K=\bar K$, we consider the growth of the number of irreducible factors of $V^{\otimes n}$ when $n$ is large. We prove that there exist…

Representation Theory · Mathematics 2025-12-30 Michael J. Larsen

We study irreducible restrictions from modules over symmetric groups to subgroups. We get reduction results which substantially restrict the classes of subgroups and modules for which this is possible. Such results are known when the…

Representation Theory · Mathematics 2018-10-08 Alexander Kleshchev , Lucia Morotti , Pham Huu Tiep

Let $q$ be a prime power and $F_4(q)$ be the Chevalley group of type $F_4$ over a finite field with $q$ elements. Marcelo--Shinoda (1995) determined the values of the unipotent characters of $F_4(q)$ on all unipotent elements, extending…

Representation Theory · Mathematics 2023-03-14 Meinolf Geck

Let $n$ and $k$ be natural numbers such that $2^k < n$. We study the restriction to $\mathfrak{S}_{n-2^k}$ of odd-degree irreducible characters of the symmetric group $\mathfrak{S}_n$. This analysis completes the study begun in [Ayyer A.,…

Representation Theory · Mathematics 2017-09-06 Christine Bessenrodt , Eugenio Giannelli , Jorn B. Olsson

We formulate and establish a super duality which connects parabolic categories $O$ between the ortho-symplectic Lie superalgebras and classical Lie algebras of $BCD$ types. This provides a complete and conceptual solution of the irreducible…

Representation Theory · Mathematics 2011-02-01 Shun-Jen Cheng , Ngau Lam , Weiqiang Wang

We prove that when $q$ is a power of $2$, every complex irreducible representation of $\mathrm{Sp}(2n, \mathbb{F}_q)$ may be defined over the real numbers, that is, all Frobenius-Schur indicators are 1. We also obtain a generating function…

Representation Theory · Mathematics 2017-08-25 C. Ryan Vinroot

The purpose of this paper is to define a set of representations of Sp(p,q) and SO*(2n), the unipotent representations of the title, and establish their unitarity. The unipotent representations considered here properly contain the special…

Representation Theory · Mathematics 2018-06-21 Dan M. Barbasch , Peter E. Trapa

In this paper we consider the restriction of a unitary irreducible representation of type $A_{\mathfrak q}(\lambda)$ of $GL(4,{\mathbb R})$ to reductive subgroups $H$ which are the fixpoint sets of an involution. We obtain a formula for the…

Representation Theory · Mathematics 2008-04-25 Bent Orsted , Birgit Speh

We characterise finite groups such that for an odd prime $p$ all the irreducible characters in its principal $p$-block have odd degree. We show that this situation does not occur in non-abelian simple groups of order divisible by $p$ unless…

Representation Theory · Mathematics 2017-10-05 Eugenio Giannelli , Gunter Malle , Carolina Vallejo

We classify the finite-dimensional irreducible linear representations of the Baumslag-Solitar groups BS(p,q) = < a, b | a b^p = b^q a > for relatively prime p and q. The general strategy of the argument is to consider the matrix group given…

Group Theory · Mathematics 2012-09-19 Daniel McLaury

For a block B of a finite group G there are well-known orthogonality relations for the generalized decomposition numbers. We refine these relations by expressing the generalized decomposition numbers with respect to an integral basis of a…

Representation Theory · Mathematics 2015-11-23 Benjamin Sambale

Applying the embedding of $A_{n-1}$ in $B_n$, $C_n$ and $D_n$ we construct a new supercharacter theory for the Sylow subgroups in orthogonal and symplectic groups over a finite field. The constructed supercharacter appears to be a little…

Representation Theory · Mathematics 2018-08-28 A. N. Panov

Let G be a p-solvable group, P a p-subgroup and chi in Irr(G) such that chi(1)_p \ge |G:P|_p. We prove that the restriction chi_P is a sum of characters induced from subgroups Q\le P such that chi(1)_p=|G:Q|_p. This generalizes previous…

Representation Theory · Mathematics 2021-07-23 Damiano Rossi , Benjamin Sambale