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Gcharacter tables of a finite group G were defined before. These tables can be very useful to obtain certain structural information of a normal subgroup from the character table of G. We analyze certain structural properties of normal…

Group Theory · Mathematics 2024-04-29 Zeinab Akhlaghi , Maria Jose Felipe , Kelly Jean-Philippe

If $n>4$ and $c(\theta)$ denotes the set of irreducible constituents of a character $\theta$, then $c(\chi^k)={\rm Irr}(S_n)$ for all nonlinear $\chi\in {\rm Irr}(S_n)$ if and only if $k\geq n-1$.

Representation Theory · Mathematics 2025-03-13 Alexander R. Miller

Given a finite group $G$ and an irreducible complex character $\chi$ of $G$, the codegree of $\chi$ is defined as the integer ${\rm cod}(\chi)=|G:\ker\chi|/\chi(1)$. It was conjectured by G. Qian in [13] that, for every element $g$ of $G$,…

Group Theory · Mathematics 2023-06-16 Z. Akhlaghi , E. Pacifici , L. Sanus

We study the zero-sharing behavior among irreducible characters of a finite group. For symmetric groups $S_n$, it is proved that, with one exception, any two irreducible characters have at least one common zero. To further explore this…

Group Theory · Mathematics 2024-11-20 Nguyen N. Hung , Alexander Moretó , Lucia Morotti

We will describe the relationship between the indecomposable characters of the finitary symmetric group and its ergodic invariant random subgroups; and we will interpret each Thoma character as an asymptotic limit of a naturally associated…

Group Theory · Mathematics 2018-12-07 Simon Thomas

This is an exposition of our joint work with Kakde, Silliman, and Wang, in which we prove a version of Ribet's Lemma for $\mathrm{GL}_2$ in the residually indistinguishable case. We suppose we are given a Galois representation taking values…

Number Theory · Mathematics 2023-10-26 Samit Dasgupta

We prove that the number of irreducible real characters in a nilpotent block of a finite group is locally determined. We further conjecture that the Frobenius-Schur indicators of those characters can be computed for p=2 in terms of the…

Representation Theory · Mathematics 2023-02-01 Benjamin Sambale

For a finite group $G$, let $\Delta(G)$ denote the character graph built on the set of degrees of the irreducible complex characters of $G$. In this paper, we show that if the diameter of $\Delta(G)$ is equal to three, then the complement…

Group Theory · Mathematics 2019-09-10 Mahdi Ebrahimi

We define the notion of a semicharacter of a group G : A function from the group to C*, whose restriction to any abelian subgroup is a homomorphism. We conjecture that for any finite group, the order of the group of semicharacters is…

Group Theory · Mathematics 2013-11-12 Gil Alon

Let $p$ be a prime divisor of the order of a finite group $G$. Then $G$ has at least $2 \sqrt{p-1}$ complex irreducible characters of degrees prime to $p$. In case $p$ is a prime with $\sqrt{p-1}$ an integer this bound is sharp for…

Group Theory · Mathematics 2014-12-25 Gunter Malle , Attila Maróti

Suppose that $G$ is a finite group and $H$ is a nilpotent subgroup of $G$. If a character of $H$ induces an irreducible character of $G$, then the generalized Fitting subgroup of $G$ is nilpotent.

Representation Theory · Mathematics 2019-02-27 Zoltan Halasi , Attila Maroti , Gabriel Navarro , Pham Huu Tiep

Let G be an arithmetic lattice in a semisimple algebraic group over a number field. We show that if G has the congruence subgroup property, then the number of n-dimensional irreducible representations of G grows like n^a, where a is a…

Group Theory · Mathematics 2008-03-11 Nir Avni

We establish vanishing results for limits of characters in various discrete groups, most notably irreducible lattices in higher rank semisimple Lie groups. As an application, we show that any sequence of finite-dimensional representations…

Group Theory · Mathematics 2024-06-18 Arie Levit , Raz Slutsky , Itamar Vigdorovich

Given a finite group $G$, we denote by $\nu(G)$ the probability that two randomly chosen elements of $G$ generate a nilpotent subgroup. We prove that if $\nu(G)>1/12,$ then $G$ is solvable.

Group Theory · Mathematics 2026-04-07 Andrea Lucchini

If $G$ be a finite $p$-group and $\chi$ is a non-linear irreducible character of $G$, then $\chi(1)\leq |G/Z(G)|^{\frac{1}{2}}$. In \cite{fernandez2001groups}, Fern\'{a}ndez-Alcober and Moret\'{o} obtained the relation between the character…

Group Theory · Mathematics 2024-03-25 Nabajit Talukdar , Kukil Kalpa Rajkhowa

We investigate a beautiful conjecture of T. Wilde on character values and element orders of finite groups. We reduce it to a statement on nearly simple groups that can be checked ``prime by prime". For these groups, we show that a strong…

Representation Theory · Mathematics 2026-05-07 Gunter Malle , Gabriel Navarro , Pham Huu Tiep

Let G be a finite non-abelian simple group and let p be a prime. We classify all pairs (G,p) such that the sum of the complex irreducible character degrees of G is greater than the index of a Sylow p-subgroup of G. Our classification…

Group Theory · Mathematics 2013-02-07 Pablo Spiga , Alexandre Zalesski

We extend the Howlett-Isaacs theorem on the solvability of groups of central type taking into account actions by automorphisms. Then we study certain induced characters whose constituents have all the same degree.

Representation Theory · Mathematics 2016-09-02 Gabriel Navarro , Noelia Rizo

If G is a finite group and H is a subgroup of G, we characterize when restriction of Brauer characters from G to H is injective.

Representation Theory · Mathematics 2017-05-01 Gabriel Navarro

The character codegree of an irreducible character of a finite group $G$ is given by the index of its kernel in $G$ upon the character degree. We compute the codegrees of irreducible characters of VZ and Camina $p$-groups, and also obtain…

Group Theory · Mathematics 2026-05-26 Ayush Udeep