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Related papers: String $C$-groups with real Schur index $2$

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Let $G$ be a group of odd order and $\chi$ be a complex irreducible character. Then there exists a unique character $\chi^{(2)}\in\Irr(G)$ such that $[\chi^2,\chi^{(2)}]$ is odd. Also, there exists a unique character $\psi\in \Irr(G)$ such…

Group Theory · Mathematics 2007-05-23 Edith Adan-Bante

The classification of irreducible, spherical characters of the infinite-dimensional unitary/orthogonal/symplectic groups can be obtained by finding all possible limits of normalized, irreducible characters of the corresponding…

Representation Theory · Mathematics 2018-12-18 Cesar Cuenca , Vadim Gorin

The present work investigates regular, semiregular, and chiral polytopes of any rank $d\geq 3$, whose automorphism groups are 2-groups. There is a large variety of rather small finite regular or alternating semiregular polytopes with…

Group Theory · Mathematics 2025-12-18 Gabriel Cunningham , Yan-Quan Feng , Dong-Dong Hou , Egon Schulte

Regular incidence complexes are combinatorial incidence structures generalizing regular convex polytopes, regular complex polytopes, various types of incidence geometries, and many other highly symmetric objects. The special case of…

Combinatorics · Mathematics 2017-11-08 Egon Schulte

We study a spectral problem related to the finite-dimensional characters of the groups $Sp(2N)$, $SO(2N+1)$, and $SO(2N)$, which form the classical series $C$, $B$, and $D$, respectively. The irreducible characters of these three series are…

Representation Theory · Mathematics 2024-07-29 Grigori Olshanski

We derive several identities that feature irreducible characters of the general linear, the symplectic, the orthogonal, and the special orthogonal groups. All the identities feature characters that are indexed by shapes that are "nearly"…

Representation Theory · Mathematics 2007-05-23 Christian Krattenthaler

Let O be a complete discrete valuation domain with finite residue field. In this paper we describe the irreducible representations of the groups Aut(M) for any finite O-module M of rank two. The main emphasis is on the interaction between…

Representation Theory · Mathematics 2008-08-21 Uri Onn

We prove that a uniquely 2-divisible group that admits an almost regular involutory automorphism is solvable.

Group Theory · Mathematics 2010-09-03 Yoav Segev

An irreducible character $\chi$ of an association scheme is called nonlinear if the multiplicity of $\chi$ is greater than $1$. The main result of this paper gives a characterization of commutative association schemes with at most two…

Combinatorics · Mathematics 2016-08-30 Javad Bagherian

A finite group $G$ is $normally ~monomial$ if all its irreducible characters are induced from linear characters of normal subgroups of $G$. In this paper, we determine all possible irreducible character degree sets of normally monomial…

Group Theory · Mathematics 2022-09-13 Dongfang Yang , Heng Lv

Using computational methods, we determine the irreducible Brauer characters of the automorphism group of the Chevalley group F_4(2), up to one parameter and one consistency issue.

Group Theory · Mathematics 2024-12-16 Gerhard Hiss , Frank Lübeck

We prove Clifford theoretic results on the representations of finite groups which only hold in characteristic $2$. Let $G$ be a finite group, let $N$ be a normal subgroup of $G$ and let $\varphi$ be an irreducible $2$-Brauer character of…

Representation Theory · Mathematics 2020-11-03 Rod Gow , John Murray

In this paper we give a non-computer-assisted proof of the following result: if $G$ is an even transitive group of degree $11$ and has a string C-group representation with rank $r\in\{4,5\}$ then $G\cong\PSL_2(11)$. Moreover this string…

Group Theory · Mathematics 2023-11-02 Maria Elisa Fernandes , Claudio Alexandre Piedade , Olivia Reade

Answering a question of J. Rosenberg, we construct the first examples of infinite characters on $GL_n(\mathbf{K})$ for a global field $\mathbf{K}$ and $n\geq 2.$ The case $n=2$ is deduced from the following more general result. Let $G$ a…

Operator Algebras · Mathematics 2018-06-28 Bachir Bekka

A method to construct irreducible unitary representations of a hyperspecial compact subgroup of a reductive group over p-adic field with odd p is presented. Our method is based upon Cliffods theory and Weil representations over finite…

Group Theory · Mathematics 2018-05-17 Koichi Takase

A finite group $G$ is called a Schur group, if any Schur ring over $G$ is the transitivity module of a point stabilizer in a subgroup of $\sym(G)$ that contains all right translations. We complete a classification of abelian $2$-groups by…

Combinatorics · Mathematics 2017-06-21 Mikhail Muzychuk , Ilya Ponomarenko

We prove a broad generalization of a theorem of W. Burnside on real characters using permutation characters. Under a necessary hypothesis, We can give some control on multiplicities (a result that needs the Classification of Finite Simple…

Group Theory · Mathematics 2021-01-08 Robert Guralnick , Gabriel Navarro

In the previous paper, we proposed a practical method of constructing explicitly representation groups $R(G)$ for finite groups $G$, and apply it to certain typical finite groups $G$ with Schur multiplier $M(G)$ containing prime number 3.…

Representation Theory · Mathematics 2024-08-30 Tatsuya Tsurii , Satoe Yamanaka , Itsumi Mikami , Takeshi Hirai

In this article it is determined which integral reflection representations of the symmetric groups and the primitive complex reflection groups of degree $2$ have rings of invariants which are isomorphic to polynomial rings.

Commutative Algebra · Mathematics 2023-03-16 David Mundelius

In this article, we consider $\mathcal{C}^\infty$-smooth real hypersurfaces of infinite type in $\mathbb C^2$. The purpose of this paper is to give explicit descriptions for stability groups of the hypersurface $M(a,\alpha,p,q)$ (see Sec.…

Complex Variables · Mathematics 2014-04-22 Ninh Van Thu