{ "id": "1510.03733", "version": "v1", "published": "2015-10-13T15:15:43.000Z", "updated": "2015-10-13T15:15:43.000Z", "title": "A finiteness condition on centralizers in locally finite groups", "authors": [ "Gustavo A. Fernandez-Alcober", "Leire Legarreta", "Antonio Tortora", "Maria Tota" ], "comment": "11 pages, submitted to an international journal. arXiv admin note: substantial text overlap with arXiv:1412.7330", "categories": [ "math.GR" ], "abstract": "We consider a finiteness condition on centralizers in a group G, namely that |C_G (x) : | is finite for every non-normal cyclic subgroup of G. For periodic groups, this is the same as |C_G (x)| is finite for every non-normal cyclic subgroup of G. We give a full description of locally finite groups satisfying this condition. As it turns out, they are a special type of cyclic extensions of Dedekind groups. We also study a variation of our condition, where the requirement of finiteness is replaced with a bound: |C_G (x) : | < n for every non-normal cyclic subgroup of G, for some fixed n. In this case, we are able to extend our analysis to the class of periodic locally graded groups.", "revisions": [ { "version": "v1", "updated": "2015-10-13T15:15:43.000Z" } ], "analyses": { "subjects": [ "20F50", "20E34" ], "keywords": [ "locally finite groups", "finiteness condition", "non-normal cyclic subgroup", "centralizers", "periodic groups" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv151003733F" } } }