English
Related papers

Related papers: Integral group rings with all central units trivia…

200 papers

The subgroup generated by all solvable normal subgroups in a pseudo-finite group with the descending chain condition on centralizers up to finite index is solvable. Additionally, there is no finitely generated pseudo-finite group whose…

Group Theory · Mathematics 2026-05-06 Nadja Hempel , Ulla Karhumäki

Which groups can occur as the group of units in a ring? Such groups are called realizable. Though the realizable members of several classes of groups have been determined (e.g., cyclic, odd order, alternating, symmetric, finite simple,…

Group Theory · Mathematics 2026-02-17 Keir Lockridge , Jacinda Terkel

The aim of this article is to explore global and local properties of finite groups whose integral group rings have only trivial central units, so-called cut groups. For such a group we study actions of Galois groups on its character table…

Group Theory · Mathematics 2021-11-10 Andreas Bächle , Mauricio Caicedo , Eric Jespers , Sugandha Maheshwary

We call a finite group irrational if none of its elements is conjugate to a distinct power of itself. We prove that those groups are solvable and describe certain classes of these groups, where the above property is only required for…

Group Theory · Mathematics 2018-07-11 Andreas Bächle , Benjamin Sambale

In this paper, in the first we give definitions of some classes of division rings which strictly contain the class of centrally finite division rings. One of our main purpose is to construct non-trivial examples of rings of new defined…

Rings and Algebras · Mathematics 2011-03-16 Bui Xuan Hai , Mai Hoang Bien , Trinh Thanh Deo

The commuting graph of a finite soluble group with trivial centre is investigated. It is shown that the diameter of such a graph is at most 8 or the graph is disconnected. Examples of soluble groups with trivial centre and commuting graph…

Group Theory · Mathematics 2014-02-26 Chris Parker

For a group $G$ and a subgroup $H$ of $G$ this article discusses the normalizer of $H$ in the units of a group ring $RG$. We prove that $H$ is only normalized by the `obvious' units, namely products of elements of $G$ normalizing $H$ and…

Group Theory · Mathematics 2017-04-20 Andreas Bächle

In this paper, it is proved that the group generated by Bass units contains a subgroup of finite index in the group of central units $\mathcal{Z}(\mathcal{U}(\mathbb{Z}G))$ of the integral group ring $\mathbb{Z}G$ for a subgroup closed…

Rings and Algebras · Mathematics 2021-09-22 Gurmeet K. Bakshi , Gurleen Kaur

Notes used for a course held in 2016 in the School of Advances in Group Theory and Applications, for some lectures given in 2018 for the students of the Master in Mathematics of the Vrije Universiteit Brussels, a course for master and Ph.D.…

Rings and Algebras · Mathematics 2025-11-13 Ángel del Río

All finite simple groups are determined with the property that every Galois orbit on conjugacy classes has size at most 4. From this we list all finite simple groups $G$ for which the normalized group of central units of the integral group…

Group Theory · Mathematics 2019-06-04 Victor Bovdi , Thomas Breuer , Attila Maróti

We give an explicit description for a basis of a subgroup of finite index in the group of central units of the integral group ring $\Z G$ of a finite abelian-by-supersolvable group such that every cyclic subgroup of order not a divisor of 4…

Rings and Algebras · Mathematics 2012-07-06 Eric Jespers , Gabriela Olteanu , Ángel del Río , Inneke Van Gelder

In this report we summarize this work, all finite simple groups $G$ can determined uniformly using their orders $|G|$ and the set $\pi_e(G)$ of their element orders.

Group Theory · Mathematics 2013-03-19 Wujie Shi

In this paper, we describe finite, additively commutative, congruence simple semirings. The main result is that the only such semirings are those of order 2, zero-multiplication rings of prime order, matrix rings over finite fields, those…

Rings and Algebras · Mathematics 2007-05-23 Chris Monico

We present a method to explicitly compute a complete set of orthogonal primitive idempotents in a simple component with Schur index 1 of a rational group algebra $\mathbb{Q}G$ for $G$ a finite generalized strongly monomial group. For the…

Rings and Algebras · Mathematics 2024-01-17 Gurmeet K. Bakshi , Jyoti Garg , Gabriela Olteanu

In this paper we prove that free solvable groups have finite Krull dimension. In fact, this is true for much wider class of solvable groups, termed rigid groups. Along the way we study the algebraic structure of the limit solvable groups…

Group Theory · Mathematics 2008-08-22 A. Myasnikov , N. Romanovskiy

The following results are proved: The center of any finite index subgroup of an irreducible, infinite, non-affine Coxeter group is trivial; Any finite index subgroup of an irreducible, infinite, non-affine Coxeter group cannot be expressed…

Group Theory · Mathematics 2007-05-23 Dongwen Qi

We consider the question whether a Sylow like theorem is valid in the normalized units of integral group rings of finite groups. After a short survey on the known results we show that this is the case for integral group rings of Frobenius…

Rings and Algebras · Mathematics 2016-06-01 Wolfgang Kimmerle , Leo Margolis

We restrict the type of $2 \times 2$-matrices which can occur as simple components in the Wedderburn decomposition of the rational group algebra of a finite group. This results in a description up to commensurability of the group of units…

Group Theory · Mathematics 2014-09-18 Florian Eisele , Ann Kiefer , Inneke Van Gelder

A finite group $G$ is called uniformly semi-rational if there exists an integer $r$ such that the generators of every cyclic sugroup $\langle x \rangle$ of $G$ lie in at most two conjugacy classes, namely $x^G$ or $(x^r)^G$. In this paper,…

Group Theory · Mathematics 2024-10-16 Marco Vergani

We describe the primitive central idempotents of the group algebra over a number field of finite monomial groups. We give also a description of the Wedderburn decomposition of the group algebra over a number field for finite strongly…

Representation Theory · Mathematics 2014-11-24 Gabriela Olteanu , Inneke Van Gelder