{ "id": "0808.2087", "version": "v1", "published": "2008-08-15T03:45:27.000Z", "updated": "2008-08-15T03:45:27.000Z", "title": "Connectivity Properties of Horospheres in Euclidean Buildings and Applications to Finiteness Properties of Discrete Groups", "authors": [ "Kai-Uwe Bux", "Kevin Wortman" ], "comment": "27 pages", "categories": [ "math.GR", "math.GT" ], "abstract": "Let G(O_S) be an S-arithmetic subgroup of a connected, absolutely almost simple linear algebraic group G over a global function field K. We show that the sum of local ranks of G determines the homological finiteness properties of G(O_S) provided the K-rank of G is 1. This shows that the general upper bound for the finiteness length of G(O_S) established in an earlier paper is sharp in this case. The geometric analysis underlying our result determines the conectivity properties of horospheres in thick Euclidean buildings.", "revisions": [ { "version": "v1", "updated": "2008-08-15T03:45:27.000Z" } ], "analyses": { "subjects": [ "20G30", "20E42", "20F65" ], "keywords": [ "finiteness properties", "discrete groups", "connectivity properties", "horospheres", "applications" ], "note": { "typesetting": "TeX", "pages": 27, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2008arXiv0808.2087B" } } }