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Let $G$ be a closed highly homogeneous subgroup of $S_{\infty}$ not involving circular orderings. We show that the closure of a conjugacy class from $G$ contains a conjugacy class which is comeagre in it. Furthermore, we show that the…

Logic · Mathematics 2025-04-23 Monika Drzewiecka , Aleksander Ivanov , Bartosz Mokry

We offer a criterion for showing that the automorphism group of an ultrahomogeneous structure is topologically 2-generated and even has a cyclically dense conjugacy class. We then show how finite topological rank of the automorphism group…

Group Theory · Mathematics 2019-08-26 Itay Kaplan , Pierre Simon

We attach a ring of sequences to each number from a certain class of extremal real numbers, and we study the properties of this ring both from an analytic point of view by exhibiting elements with specific behaviors, and also from an…

Number Theory · Mathematics 2013-01-07 Damien Roy , Eric Villani

Every mathematician is familiar with the beautiful structure of finite commutative groups. What is less well known is that finite commutative semigroups also have a neat and well-described structure. We prove this in an efficient fashion.…

Group Theory · Mathematics 2025-05-02 Marcel Wild

Residual finiteness growth measures how well-approximated a group is by its finite quotients. We prove that some related growth functions characterize linearity for a class of groups including all hyperbolic groups.

Group Theory · Mathematics 2016-11-16 Khalid Bou-Rabee , D. B. McReynolds

Arithmetical properties of a finite group are properties of the group which are defined by its arithmetical parameters such as the order of the group, the element orders and so on. In this paper, we discuss a number of results on…

Group Theory · Mathematics 2025-04-22 Natalia V. Maslova

A connected component of an affine algebraic group is called periodic if all its elements have finite order. We give a characterization of periodic components in terms of automorphisms with finite number of fixed points. It is also…

Algebraic Geometry · Mathematics 2015-05-13 S. N. Fedotov

We prove that bounded conciseness is a closed property in the space of marked groups. As a consequence, we reformulate a conjecture of Fern\'andez-Alcober and Shumyatsky [7] about conciseness in the class of residually finite groups.

Group Theory · Mathematics 2025-02-10 Federico Berlai

There is a well-known classification of conjugacy classes of involutions in finite Coxeter groups, in terms of subsets of nodes of their Coxeter graphs. In many cases, the product of an involution with the longest element is again an…

Group Theory · Mathematics 2022-02-10 Marcus Zibrowius

A group is nested if the centers of the irreducible characters form a chain. In this paper, we will show that there is a set of subgroups associated with the conjugacy classes of group so that a group is nested if and only if these…

Group Theory · Mathematics 2019-10-10 Shawn T. Burkett , Mark L. Lewis

The well-known Landau's theorem states that, for any positive integer $k$, there are finitely many isomorphism classes of finite groups with exactly $k$ (conjugacy) classes. We study variations of this theorem for $p$-regular classes as…

Group Theory · Mathematics 2015-03-27 Alexander Moreto , Hung Ngoc Nguyen

Let $G$ be a real reductive group in Harish-Chandra's class. We derive some consequences of theory of coherent continuation representations to the counting of irreducible representations of $G$ with a given infinitesimal character and a…

Representation Theory · Mathematics 2025-01-03 Dan Barbasch , Jia-Jun Ma , Binyong Sun , Chen-Bo Zhu

We prove certain polynomial relations between the values of complex irreducible characters of general finite symmetric groups. We use it to find some sets of conjugacy classes such that no finite symmetric group has a complex irreducible…

Representation Theory · Mathematics 2026-01-19 Lee Tae Young

We give a concrete characterization of the rational conjugacy classes of maximal tori in groups of type $D_n$, with specific emphasis on the case of number fields and p-adic fields. This includes the forms associated to quadratic spaces,…

Group Theory · Mathematics 2020-05-11 Andrew Fiori

The classification of finite simple strongly real groups is complete. It is easy to see that strong reality for every nonabelian finite simple group is equivalent to the fact that each element can be written as a product of two involutions.…

Group Theory · Mathematics 2010-09-07 E. P. Vdovin , A. A. Gal't

In this note, we formulate an observation that "almost all" irreducible ordinary characters of finite groups of Lie type remain irreducible when restricted to the derived subgroups. To see this, key ingredients are some asymptotic results…

Representation Theory · Mathematics 2021-07-08 Conghui Li

Explainable machine learning methods have been accompanied by substantial development. Despite their success, the existing approaches focus more on the general framework with no prior domain expertise. High-stakes financial sectors have…

Computational Finance · Quantitative Finance 2024-08-13 Dangxing Chen , Jingfeng Chen , Weicheng Ye

Let G' be a connected reductive group over the complex numbers. We show that the set of conjugacy classes of G' is in natural bijection with the set of two-sided cells associated to a certain algebra.

Representation Theory · Mathematics 2017-06-09 G. Lusztig

Positive definite functions on spheres have received an increasing interest in many branches of mathematics and statistics. In particular, the Schoenberg sequences in the spectral representation of positive definite functions have been…

Classical Analysis and ODEs · Mathematics 2019-01-24 Pier Giovanni Bissiri , Valdir A. Menegatto , Emilio Porcu

This work focuses on the combinatorial properties of glued semigroups and provides its combinatorial characterization. Some classical results for affine glued semigroups are generalized and some methods to obtain glued semigroups are…

Commutative Algebra · Mathematics 2015-03-19 J. I. García-García , M. A. Moreno-Frías , A. Vigneron-Tenorio