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Related papers: Groups with a nontrivial nonideal kernel

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We prove that if $G$ is a finite simple group which is the unit group of a ring, then $G$ is isomorphic to either (a) a cyclic group of order 2; (b) a cyclic group of prime order $2^k -1$ for some $k$; or (c) a projective special linear…

Rings and Algebras · Mathematics 2015-02-02 Christopher Davis , Tommy Occhipinti

For any finite group Q not of prime power order, we construct a group G that is virtually of type F, contains infinitely many conjugacy classes of subgroups isomorphic to Q, and contains only finitely many conjugacy classes of other finite…

Group Theory · Mathematics 2014-11-11 Ian J Leary

We classify, up to equivalence, all finite-dimensional simple graded division algebras over the field of real numbers. The grading group is any finite abelian group.

Rings and Algebras · Mathematics 2015-06-09 Yuri Bahturin , Mikhail Zaicev

In this article we introduce and study a class of finite groups for which the orders of normal subgroups satisfy a certain inequality. It is closely connected to some well-known arithmetic classes of natural numbers.

Group Theory · Mathematics 2018-05-31 Marius Tărnăuceanu

A graph product kernel means the kernel of the natural surjection from a graph product to the corresponding direct product. We prove that a graph product kernel of countable groups is special, and a graph product of finite or cyclic groups…

Group Theory · Mathematics 2012-05-17 Sang-hyun Kim

For $R_1,R_2,R_3,\dots$ a family of non isomorphic rings (or algebras) having each only 2 idempotents ($1$ and $0$), we classify up to isomorphism the rings (or algebras) obtained by taking products of powers of the different $R_i$. We show…

Rings and Algebras · Mathematics 2025-12-24 Mohamad Maassarani

We classify those sequences $\langle S_{n} \mid n \in \mathbb{N} \rangle$ of finite simple nonabelian groups such that the full product $\prod_{n} S_{n}$ has property (FA).

Group Theory · Mathematics 2008-02-03 Jan Saxl , Saharon Shelah , Simon Thomas

We give an algorithm to determine finitely many generators for a subgroup of finite index in the unit group of an integral group ring $\mathbb{Z} G$ of a finite nilpotent group $G$, this provided the rational group algebra $\mathbb{Q} G$…

When considering the unit group of $\mathcal{O}_F G$ ($\mathcal{O}_F$ the ring of integers of an abelian number field $F$ and a finite group $G$) certain components in the Wedderburn decomposition of $FG$ cause problems for known generic…

Representation Theory · Mathematics 2016-06-07 Andreas Bächle , Mauricio Caicedo , Inneke Van Gelder

We consider the natural Lie algebra structure on the (associative) group algebra of a finite group $G$, and show that the Lie subalgebras associated to natural involutive antiautomorphisms of this group algebra are reductive ones. We give a…

Representation Theory · Mathematics 2008-09-02 Ivan Marin

We give a full classification, up to equivalence, of finite-dimensional graded division algebras over the field of real numbers. The grading group is any abelian group.

Rings and Algebras · Mathematics 2018-03-06 Yuri Bahturin , Mikhail Zaicev

Let $\mathcal{C}$ be a class of finite groups closed for subgroups, quotients groups and extensions. Let $\Gamma$ be a finite simplicial graph and $G = G_{\Gamma}$ be the corresponding pro-$\mathcal C$ RAAG. We show that if $N$ is a…

Group Theory · Mathematics 2023-05-08 Dessislava Kochloukova , Pavel Zalesskii

Let $R$ be a commutative ring and $\Gamma$ be an infinite discrete group. The algebraic $K$-theory of the group ring $R[\Gamma]$ is an important object of computation in geometric topology and number theory. When the group ring is…

K-Theory and Homology · Mathematics 2016-07-04 Gunnar Carlsson , Boris Goldfarb

This paper classifies the derivations of group algebras in terms of the generators and defining relations of the group. If $RG$ is a group ring, where $R$ is commutative and $S$ is a set of generators of $G$ then necessary and sufficient…

Rings and Algebras · Mathematics 2018-12-05 Kieran Hughes , Leo Creedon

In a series of recent contributions on the notion of global breadth $\mathbf{B}(G)$ of a finite group $G$, it was interesting to observe the structural conditions arising from the classification of finite groups of $\mathbf{B}(G)=8$. This…

Group Theory · Mathematics 2025-06-25 Seid Kassaw Muhie , Daniele Ettore Otera , Francesco G. Russo

We classify the finite groups $G$ which satisfies the condition that every complex irreducible character,whose degree's square doesn't divide the index of its kernel in $G$, lies in the same Galois conjugacy class.

Group Theory · Mathematics 2022-08-17 Yu Zeng , Dongfang Yang

Let $RG$ be the gruop ring of the group $G$ over ring $R$ and $\mathscr{U}(RG)$ be its unit group. Finding the structure of the unit group of a finite group ring is an old topic in ring theory. In, G. Tang et al: Unit Groups of Group…

Rings and Algebras · Mathematics 2020-04-08 Ali Ashja'

Let $k$ be a field. We characterize the group schemes $G$ over $k$, not necessarily affine, such that $\mathsf{D}_{\mathrm{qc}}(B_kG)$ is compactly generated. We also describe the algebraic stacks that have finite cohomological dimension in…

Algebraic Geometry · Mathematics 2016-09-08 Jack Hall , David Rydh

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

For a finite smooth algebraic group $F$ over a field $k$ and a smooth algebraic group $\bar G$ over the separable closure of $k$, we define the notion of $F$-kernel in $\bar G$ and we associate to it a set of nonabelian 2-cohomology. We use…

Group Theory · Mathematics 2018-06-04 Giancarlo Lucchini Arteche