ﻻ يوجد ملخص باللغة العربية
Let $G$ be a finite group of odd order admitting an involutory automorphism $phi$. We obtain two results bounding the exponent of $[G,phi]$. Denote by $G_{-phi}$ the set ${[g,phi],vert, gin G}$ and by $G_{phi}$ the centralizer of $phi$, that is, the subgroup of fixed points of $phi$. The obtained results are as follows.1. Assume that the subgroup $langle x,yrangle$ has derived length at most $d$ and $x^e=1$ for every $x,yin G_{-phi}$. Suppose that $G_phi$ is nilpotent of class $c$. Then the exponent of $[G,phi]$ is $(c,d,e)$-bounded.2. Assume that $G_phi$ has rank $r$ and $x^e=1$ for each $xin G_{-phi}$. Then the exponent of $[G,phi]$ is $(e,r)$-bounded.
Let $G$ be a finite group admitting a coprime automorphism $phi$ of order $n$. Denote by $G_{phi}$ the centralizer of $phi$ in $G$ and by $G_{-phi}$ the set ${ x^{-1}x^{phi}; xin G}$. We prove the following results. 1. If every element from $G_{ph
In this article we present an extensive survey on the developments in the theory of non-abelian finite groups with abelian automorphism groups, and pose some problems and further research directions.
We study fixed point properties of the automorphism group of the universal Coxeter group Aut$(W_n)$. In particular, we prove that whenever Aut$(W_n)$ acts by isometries on complete $d$-dimensional CAT$(0)$ space with $d<lfloorfrac{n}{2}rfloor$, then
We prove that the automorphism group of the braid group on four strands acts faithfully and geometrically on a CAT(0) 2-complex. This implies that the automorphism group of the free group of rank two acts faithfully and geometrically on a CAT(0) 2-co
A family $mathcal L$ of subsets of a set $X$ is called linked if $Acap B eemptyset$ for any $A,Binmathcal L$. A linked family $mathcal M$ of subsets of $X$ is maximal linked if $mathcal M$ coincides with each linked family $mathcal L$ on $X$ that con