English
Related papers

Related papers: Centralizers in pseudo-finite groups

200 papers

We give a structural theorem for pseudofinite groups of finite centraliser dimension. As a corollary, we observe that there is no finitely generated pseudofinite group of finite centraliser dimension.

Logic · Mathematics 2021-06-11 Ulla Karhumäki

Locally finite groups having the property that every non-cyclic subgroup contains its centralizer are completely classified.

Group Theory · Mathematics 2016-06-07 Costantino Delizia , Urban Jezernik , Primoz Moravec , Chiara Nicotera , Chris Parker

In this paper we find a necessary and sufficient condition for a finite nilpotent group to have an abelian central automorphism group.

Group Theory · Mathematics 2007-05-23 Ayan Mahalanobis

A group $G$ is said to have restricted centralizers if for each $g$ in $G$ the centralizer $C_G(g)$ either is finite or has finite index in $G$. Shalev showed that a profinite group with restricted centralizers is virtually abelian. Given a…

Group Theory · Mathematics 2021-12-30 Cristina Acciarri , Pavel Shumyatsky

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

This paper investigates the finite generation of cluster automorphism groups. By applying the pseudo $\mathbb{N}$-grading introduced in our previous work, we establish a sufficient condition for a cluster automorphism group to be finitely…

Rings and Algebras · Mathematics 2026-05-28 Changjian Fu , Zhanhong Liang , Yinzhi Wang

We study the automorphism group of the algebraic closure of a substructure A of a pseudo-finite field F. We show that the behavior of this group, even when A is large, depends essentially on the roots of unity in F. For almost all…

Logic · Mathematics 2012-01-16 Özlem Beyarslan , Ehud Hrushovski

It is shown that a finite group in which more than 3/4 of the elements are involutions must be an elementary abelian 2-group. A group in which exactly 3/4 of the elements are involutions is characterized as the direct product of the…

Group Theory · Mathematics 2009-11-09 Allan L. Edmonds , Zachary B. Norwood

Working in a theory with an integer-valued dimension on interpretable sets, we classify pseudofinite definably primitive permutation groups acting on one-dimensional sets which satisfy a version of chain condition on centralizers and on…

Logic · Mathematics 2020-07-21 Tingxiang Zou

Let $K$ be a field and $f:\mathbb{P}^N \to \mathbb{P}^N$ a morphism. There is a natural conjugation action on the space of such morphisms by elements of the projective linear group $\text{PGL}_{N+1}$. The group of automorphisms, or…

Number Theory · Mathematics 2016-04-12 Joao Alberto de Faria , Benjamin Hutz

The generalised Fitting subgroup of a finite group is the group generated by all subnormal subgroups that are either nilpotent or quasisimple. The importance of this subgroup in finite group theory stems from the fact that it always…

Group Theory · Mathematics 2009-04-03 Colin Reid

We analyse the complexity of constructing involution centralisers in unitary groups over fields of odd order. In particular, we prove logarithmic bounds on the number of random elements required to generate a subgroup of the centraliser of…

Group Theory · Mathematics 2019-09-23 S. P. Glasby , Cheryl E. Praeger , Colva M. Roney-Dougal

We characterize finite $p$-groups $G$ of order up to $p^7$ for which the group of central automorphisms fixing the center element-wise is of minimum possibe order.

Group Theory · Mathematics 2015-03-17 Deepak Gumber , Mahak Sharma

We study equalizers and fixed points of monomorphisms of free groups at infinity. We show that the action of the equalizer of two monomorphisms on the regular points of the equalizer at infinity has finitely many orbits, showing that the…

Group Theory · Mathematics 2026-04-02 André Carvalho , Pedro V. Silva

Heisenberg groups over algebras with central involution and their automorphism groups are constructed. The complex quaternion group algebra over a prime field is used as an example. Its subspaces provide finite models for each of the real…

Mathematical Physics · Physics 2015-09-30 Robert W. Johnson

Finite groups with very few character values are characterized. The following is the main result of this article: a finite non-abelian group has precisely four character values if and only if it is the generalized dihedral group of a…

Group Theory · Mathematics 2021-03-16 Taro Sakurai

A group is called a CA-group if the centralizer of every non-central element is abelian. Furthermore, a group is called a minimal non-CA-group if it is not a CA-group itself, but all of its proper subgroups are. In this paper, we give a…

Group Theory · Mathematics 2019-12-18 L. Jafari , S. Kohl , M. Zarrin

A group is called metahamiltonian if all non-abelian subgroups of it are normal. This concept is a natural generation of Hamiltonian groups. In this paper, a complete classification of finite metahamiltonian $p$-groups is given.

Group Theory · Mathematics 2017-08-17 Xingui Fang , Lijian An

We give a classification of maximal elements of the set of finite groups that can be realized as the automorphism groups of polarized abelian threefolds over finite fields.

Number Theory · Mathematics 2020-11-24 WonTae Hwang , Bo-Hae Im , Hansol Kim

A group is metabelian if its commutator subgroup is abelian. For finitely generated metabelian groups, classical commutative algebra, algebraic geometry and geometric group theory, especially the latter two subjects, can be brought to bear…

Group Theory · Mathematics 2012-03-27 Gilbert Baumslag , Roman Mikhailov , Kent E. Orr