{ "id": "1007.0418", "version": "v1", "published": "2010-07-02T18:09:17.000Z", "updated": "2010-07-02T18:09:17.000Z", "title": "Star clusters in independence complexes of graphs", "authors": [ "Jonathan Ariel Barmak" ], "comment": "22 pages, 13 figures", "categories": [ "math.CO", "math.AT" ], "abstract": "We introduce the notion of \\textit{star cluster} of a simplex in a simplicial complex. This concept provides a general tool to study the topology of independence complexes of graphs. We use star clusters to answer a question arisen from works of Engstr\\\"om and Jonsson on the homotopy type of independence complexes of triangle-free graphs and to investigate a large number of examples which appear in the literature. We present an alternative way to study the chromatic number of a graph from a homotopical point of view and obtain new results regarding the connectivity of independence complexes.", "revisions": [ { "version": "v1", "updated": "2010-07-02T18:09:17.000Z" } ], "analyses": { "subjects": [ "57M15", "05C69", "55P15", "05C10" ], "keywords": [ "independence complexes", "star clusters", "general tool", "simplicial complex", "homotopy type" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010arXiv1007.0418B" } } }