{ "id": "1010.0343", "version": "v1", "published": "2010-10-02T14:57:41.000Z", "updated": "2010-10-02T14:57:41.000Z", "title": "Frobenius groups of automorphisms and their fixed points", "authors": [ "Evgenii I. Khukhro", "Natalia Yu. Makarenko", "Pavel Shumyatsky" ], "comment": "31 pages", "doi": "10.1515/form.2011.152", "categories": [ "math.GR", "math.RA" ], "abstract": "Suppose that a finite group $G$ admits a Frobenius group of automorphisms $FH$ with kernel $F$ and complement $H$ such that the fixed-point subgroup of $F$ is trivial: $C_G(F)=1$. In this situation various properties of $G$ are shown to be close to the corresponding properties of $C_G(H)$. By using Clifford's theorem it is proved that the order $|G|$ is bounded in terms of $|H|$ and $|C_G(H)|$, the rank of $G$ is bounded in terms of $|H|$ and the rank of $C_G(H)$, and that $G$ is nilpotent if $C_G(H)$ is nilpotent. Lie ring methods are used for bounding the exponent and the nilpotency class of $G$ in the case of metacyclic $FH$. The exponent of $G$ is bounded in terms of $|FH|$ and the exponent of $C_G(H)$ by using Lazard's Lie algebra associated with the Jennings--Zassenhaus filtration and its connection with powerful subgroups. The nilpotency class of $G$ is bounded in terms of $|H|$ and the nilpotency class of $C_G(H)$ by considering Lie rings with a finite cyclic grading satisfying a certain `selective nilpotency' condition. The latter technique also yields similar results bounding the nilpotency class of Lie rings and algebras with a metacyclic Frobenius group of automorphisms, with corollaries for connected Lie groups and torsion-free locally nilpotent groups with such groups of automorphisms. Examples show that such nilpotency results are no longer true for non-metacyclic Frobenius groups of automorphisms.", "revisions": [ { "version": "v1", "updated": "2010-10-02T14:57:41.000Z" } ], "analyses": { "subjects": [ "17B40", "20D45", "17B70", "20D15", "20E36", "20F40", "22E25" ], "keywords": [ "automorphisms", "nilpotency class", "fixed points", "non-metacyclic frobenius groups", "torsion-free locally nilpotent groups" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 31, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1010.0343K" } } }