English
Related papers

Related papers: Above Isaacs' Head Characters

200 papers

For an arbitrary prime $p$ we prove that the proportion of entries divisible by $p$ in certain columns of the character table of the symmetric group $S_n$ tends to 1 as $n\to\infty$. This is done by finding lower bounds on the number of…

Combinatorics · Mathematics 2019-10-31 Lucia Morotti

Let $G$ be a finite group and $N<G$ a normal subgroup with $G/N$ abelian. We show how the conjugacy classes of $G$ in a given coset $qN$ relate to the irreducible characters of $G$ that are not identically $0$ on $qN$. We describe several…

Group Theory · Mathematics 2026-01-13 Tim Dokchitser , Vladimir Dokchitser

We restrict irreducible characters of alternating groups of degree divisible by $p$ to their Sylow $p$-subgroups and study the number of linear constituents.

Representation Theory · Mathematics 2018-06-07 Eugenio Giannelli

Let N be a finite group of odd order and A a finite group that acts on N such that the orders of N and A are coprime. Isaacs constructed a natural correspondence between the set Irr_A(N) of irreducible complex characters invariant under the…

Group Theory · Mathematics 2011-08-19 Frieder Ladisch

Let N be a minimal normal nonabelian subgroup of a finite group G. We will show that there exists a nontrivial irreducible character of N of degree at least 5 which is extendible to G. This result will be used to settle two open questions…

Group Theory · Mathematics 2010-04-16 Kay Magaard , Hung P. Tong-Viet

It is known that extreme characters of several inductive limits of compact groups exhibit multiplicativity in a certain sense. In the paper, we formulate such multiplicativity for inductive limit quantum groups and provide explicit examples…

Representation Theory · Mathematics 2023-10-06 Ryosuke Sato

Let $G$ be a finite group, let $N$ be a normal subgroup of $G$ and let $\theta$ be an irreducible character of $N$. We count the real irreducible characters of $G$ lying over $\theta$

Group Theory · Mathematics 2023-01-04 John C. Murray

A subgroup $H$ of a topological abelian group $X$ is said to be characterized by a sequence $\mathbf v =(v_n)$ of characters of $X$ if $H=\{x\in X:v_n(x)\to 0\ \text{in}\ \mathbb T\}$. We study the basic properties of characterized…

General Topology · Mathematics 2015-09-04 Dikran Dikranjan , Anna Giordano Bruno , Daniele Impieri

We develop a character approach to study the invariant von Neumann subalgebras rigidity property (abbreviated as the ISR property) introduced in Amrutam-Jiang's work. First, we introduce the non-factorizable regular character property for…

Operator Algebras · Mathematics 2025-05-21 Artem Dudko , Yongle Jiang

We study the intermediate extension of the character sheaves on an adjoint group to the semi-stable locus of its wonderful compactification. We show that the intermediate extension can be described by a direct image construction. As a…

Representation Theory · Mathematics 2009-07-03 Xuhua He

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

In this paper we consider the inductive Alperin--McKay condition for isolated blocks of groups of Lie type $B$ and $C$. This finishes the verification of the inductive condition for groups of this type.

Group Theory · Mathematics 2023-07-28 Julian Brough , Lucas Ruhstorfer

We prove that a knowledge of the character degrees of a finite group G and of their multiplicities determines whether G has a Sylow p-subgroup as a direct factor. An analogous result based on a knowledge of the conjugacy class sizes was…

Group Theory · Mathematics 2007-05-23 Sandro Mattarei

Let G be a finite group with Sylow p-subgroup P. We show that the character table of G determines whether P has maximal nilpotency class and whether P is a minimal non-abelian group. The latter result is obtained from a precise…

Representation Theory · Mathematics 2023-06-07 Alexander Moretó , Benjamin Sambale

In this note, we give a group-theoretic condition which is equivalent to the fact that the trivial character is the only complex irreducible character of a finite group G which is contained in the principal p-block for each prime p in a…

Group Theory · Mathematics 2024-07-30 Geoffrey R. Robinson

We establish several new bounds for the number of conjugacy classes of a finite group, all of which involve the maximal number c of conjugacy classes of a normal subgroup fixed by some element of a suitable subset of the group. To apply…

Group Theory · Mathematics 2007-05-23 Thomas Michael Keller

We use coefficient systems on the affine Bruhat-Tits building to study admissible representations of reductive p-adic groups in characteristic not equal to p. We show that the character function is locally constant and provide explicit…

Representation Theory · Mathematics 2016-03-08 Ralf Meyer , Maarten Solleveld

The Alperin-McKay conjecture relates height zero characters of an $\ell$-block with the ones of its Brauer correspondent. This conjecture has been reduced to the so-called inductive Alperin-McKay conditions about quasi-simple groups by the…

Representation Theory · Mathematics 2020-08-25 Marc Cabanes , A. A. Schaeffer Fry , Britta Späth

This is a contribution to the study of $\operatorname {Irr}(G)$ as an $\operatorname {Aut}(G)$-set for $G$ a finite quasi-simple group. Focusing on the last open case of groups of Lie type $\mathrm D$ and $^2\mathrm D$, a crucial property…

Representation Theory · Mathematics 2025-04-21 Britta Späth

I. M. Isaacs has conjectured (see \cite{isa00}) that if the product of two faithful irreducible characters of a solvable group is irreducible, then the group is cyclic. In this paper we prove a special case of the following conjecture,…

Group Theory · Mathematics 2023-05-23 Edith Adan-Bante , Maria Loukaki , Alexander Moretó