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Related papers: Algorithmic aspects of units in group rings

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In 1960 Fuchs posed the problem of characterizing the groups which are the groups of units of commutative rings. In the following years, some partial answers have been given to this question in particular cases. In this paper we address…

Rings and Algebras · Mathematics 2019-08-07 Ilaria Del Corso

The Grothendieck--Serre conjecture predicts that every generically trivial torsor under a reductive group over a regular semilocal ring is itself trivial. Extending the work of \v{C}esnavi\v{c}ius and Fedorov, we prove a non-noetherian…

Algebraic Geometry · Mathematics 2025-06-10 Arnab Kundu

Using the Luthar--Passi method, we investigate the classical Zassenhaus conjecture for the normalized unit group of the integral group ring of the Suzuki sporadic simple group Suz. As a consequence, for this group we confirm the Kimmerle's…

Rings and Algebras · Mathematics 2008-03-17 V. A. Bovdi , A. B. Konovalov , E. N. Marcos

Let A denote the algebraic closure of the rationals Q in the complex numbers C. Suppose G is a torsion-free group which contains a congruence subgroup as a normal subgroup of finite index and denote by U(G) the C-algebra of closed densely…

Rings and Algebras · Mathematics 2007-05-23 Daniel R. Farkas , Peter A. Linnell

We consider the Zassenhaus conjecture for the normalized unit group of the integral group ring of the McLaughlin sporadic group McL. As a consequence, we confirm for this group the Kimmerle's conjecture on prime graphs.

Rings and Algebras · Mathematics 2007-05-23 V. A. Bovdi , A. B. Konovalov

We consider the Zassenhaus conjecture for the normalized unit group of the integral group ring of the Mathieu sporadic group $M_{24}$. As a consequence, for this group we confirm Kimmerle's conjecture on prime graphs.

Rings and Algebras · Mathematics 2007-05-23 V. A. Bovdi , A. B. Konovalov

In this article we overview those aspects of the theory of affine semigroups and their algebras that have been relevant for our own research, and pose several open problems. Answers to these problems would contribute substantially to the…

Commutative Algebra · Mathematics 2007-05-23 Winfried Bruns , Joseph Gubeladze , Ngo Viet Trung

The three famous problems concerning units, zero-divisors and idempotents in group rings of torsion-free groups, commonly attributed to I. Kaplansky, have been around for more than 60 years and still remain open in characteristic zero. In…

Rings and Algebras · Mathematics 2023-07-21 Johan Öinert

The integral group ring $\mathbb{Z} G$ of a group $G$ has only trivial central units, if the only central units of $\mathbb{Z} G$ are $\pm z$ for $z$ in the center of $G$. We show that the order of a finite solvable group $G$ with this…

Group Theory · Mathematics 2018-07-11 Andreas Bächle

Let $G$ be a finite group, $N$ a nilpotent normal subgroup of $G$ and let $\mathrm{V}(\mathbb{\Z} G, N)$ denote the group formed by the units of the integral group ring $\mathbb{\Z} G$ of $G$ which map to the identity under the natural…

Rings and Algebras · Mathematics 2017-11-30 Leo Margolis , Ángel del Río

We carry out a study of groups $G$ in which the index of any infinite subgroup is finite. We call them restricted-finite groups and characterize finitely generated not torsion restricted-finite groups. We show that every infinite…

Group Theory · Mathematics 2023-05-02 B. Taeri , M. R. Vedadi

We investigate the classical Zassenhaus conjecture for the unit group of the integral group ring of Mathieu simple group M23 using the Luthar-Passi method. This work is a continuation of the research that we carried out for Mathieu groups…

Rings and Algebras · Mathematics 2007-05-23 V. A. Bovdi , A. B. Konovalov

Using the Luthar-Passi method, we investigate the classical Zassenhaus conjecture for the normalized unit group of the integral group ring of the Rudvalis sporadic simple group Ru. As a consequence, for this group we confirm Kimmerle's…

Rings and Algebras · Mathematics 2008-12-01 V. A. Bovdi , A. B. Konovalov

We present an algorithm for computing the structure of any submodule of the module of points of a Drinfeld $A$-module over a finite field, where $A$ is a function ring over $\mathbb F_q$. When the function ring is $A = \mathbb F_q[T]$, we…

Number Theory · Mathematics 2026-02-27 Antoine Leudière , Renate Scheidler

The integral group rings $\mathbb{Z}G$ for finite groups $G$ are precisely those fusion rings whose basis elements have Frobenius-Perron dimension 1, and each is categorifiable in the sense that it arises as the Grothendieck ring of a…

Quantum Algebra · Mathematics 2022-08-16 Andrew Schopieray

This paper is centered around the classical problem of extracting properties of a finite group $G$ from the ring isomorphism class of its integral group ring $\mathbb{Z} G$. This problem is considered via describing the unit group…

Rings and Algebras · Mathematics 2024-10-18 Geoffrey Janssens , Eric Jespers , Ofir Schnabel

H. J. Zassenhaus conjectured that any unit of finite order and augmentation one in the integral group ring of a finite group $G$ is conjugate in the rational group algebra to an element of $G$. One way to verify this is showing that such…

Rings and Algebras · Mathematics 2018-03-15 Ángel del Río , Mariano Serrano

We study fundamental groups of clique complexes associated to random graphs. We establish thresholds for their cohomological and geometric dimension and torsion. We also show that in certain regime any aspherical subcomplex of a random…

Algebraic Topology · Mathematics 2015-06-12 Armindo Costa , Michael Farber , Danijela Horak

We describe the generalized Matsuda's theorem, and some results of a Burnside ring extend a partial Burnside ring. In particular, we give isomorphism between partial Burnside rings of different groups. Moreover, we consider the relationship…

Group Theory · Mathematics 2018-06-19 M. Wakatake

Hans J. Zassenhaus conjectured that for any unit $u$ of finite order in the integral group ring of a finite group $G$ there exists a unit $a$ in the rational group algebra of $G$ such that $a^{-1}\cdot u \cdot a=\pm g$ for some $g\in G$. We…

Rings and Algebras · Mathematics 2017-11-21 Florian Eisele , Leo Margolis