{ "id": "0810.5533", "version": "v3", "published": "2008-10-30T19:55:32.000Z", "updated": "2009-07-29T13:39:27.000Z", "title": "Characterization of Line Arrangement for which the Fundamental Group of the Complement is a Direct Product of Free Groups", "authors": [ "Eliyahu Meital", "Liberman Eran", "Schaps Mary", "Teicher Mina" ], "comment": "16 pages", "categories": [ "math.AT", "math.GR", "math.GT" ], "abstract": "Kwai Man Fan proved that if the intersection lattice of a line arrangement does not contain a cycle, then the fundamental group of its complement is a direct sum of infinite and cyclic free groups. He also conjectured that the converse is true as well. The main purpose of this paper is to prove this conjecture", "revisions": [ { "version": "v3", "updated": "2009-07-29T13:39:27.000Z" } ], "analyses": { "subjects": [ "32S22", "14N30", "52C30" ], "keywords": [ "fundamental group", "line arrangement", "direct product", "complement", "characterization" ], "note": { "typesetting": "TeX", "pages": 16, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0810.5533M" } } }