{ "id": "math/0305434", "version": "v3", "published": "2003-05-30T03:58:41.000Z", "updated": "2004-01-21T22:13:58.000Z", "title": "Cluster algebras III: Upper bounds and double Bruhat cells", "authors": [ "Arkady Berenstein", "Sergey Fomin", "Andrei Zelevinsky" ], "comment": "39 pages. Minor editorial changes, a reference added. This is the final version, to appear in Duke Mathematical Journal", "categories": [ "math.RT", "math.AC", "math.AG" ], "abstract": "We continue the study of cluster algebras initiated in math.RT/0104151 and math.RA/0208229. We develop a new approach based on the notion of an upper cluster algebra, defined as an intersection of certain Laurent polynomial rings. Strengthening the Laurent phenomenon from math.RT/0104151, we show that, under an assumption of \"acyclicity\", a cluster algebra coincides with its \"upper\" counterpart, and is finitely generated. In this case, we also describe its defining ideal, and construct a standard monomial basis. We prove that the coordinate ring of any double Bruhat cell in a semisimple complex Lie group is naturally isomorphic to the upper cluster algebra explicitly defined in terms of relevant combinatorial data.", "revisions": [ { "version": "v3", "updated": "2004-01-21T22:13:58.000Z" } ], "analyses": { "keywords": [ "double bruhat cell", "upper bounds", "upper cluster algebra", "semisimple complex lie group" ], "note": { "typesetting": "TeX", "pages": 39, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2003math......5434B" } } }