{ "id": "1002.3261", "version": "v1", "published": "2010-02-17T13:21:50.000Z", "updated": "2010-02-17T13:21:50.000Z", "title": "On the convergence of cluster expansions for polymer gases", "authors": [ "Rodrigo Bissacot", "Roberto Fernández", "Aldo Procacci" ], "categories": [ "math-ph", "math.MP" ], "abstract": "We compare the different convergence criteria available for cluster expansions of polymer gases subjected to hard-core exclusions, with emphasis on polymers defined as finite subsets of a countable set (e.g. contour expansions and more generally high- and low-temperature expansions). In order of increasing strength, these criteria are: (i) Dobrushin criterion, obtained by a simple inductive argument; (ii) Gruber-Kunz criterion obtained through the use of Kirkwood-Salzburg equations, and (iii) a criterion obtained by two of us via a direct combinatorial handling of the terms of the expansion. We show that for subset polymers our sharper criterion can be proven both by a suitable adaptation of Dobrushin inductive argument and by an alternative --in fact, more elementary-- handling of the Kirkwood-Salzburg equations. In addition we show that for general abstract polymers this alternative treatment leads to the same convergence region as the inductive Dobrushin argument and, furthermore, to a systematic way to improve bounds on correlations.", "revisions": [ { "version": "v1", "updated": "2010-02-17T13:21:50.000Z" } ], "analyses": { "subjects": [ "82B20", "05A20" ], "keywords": [ "cluster expansions", "polymer gases", "kirkwood-salzburg equations", "general abstract polymers", "direct combinatorial" ], "tags": [ "journal article" ], "publication": { "doi": "10.1007/s10955-010-9956-1", "journal": "Journal of Statistical Physics", "year": 2010, "month": "May", "volume": 139, "number": 4, "pages": 598 }, "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2010JSP...139..598B" } } }