{ "id": "0904.4102", "version": "v1", "published": "2009-04-27T07:43:28.000Z", "updated": "2009-04-27T07:43:28.000Z", "title": "Approximate Identity and Arens Regularity of Some Banach Algebras", "authors": [ "Kazem Haghnejad Azar", "Abdolhamid Riazi" ], "comment": "15 page", "categories": [ "math.FA", "math.OA" ], "abstract": "Let $A$ be a Banach algebra with the second dual $A^{**}$. If $A$ has a bounded approximate identity $(=BAI)$, then $A^{**}$ is unital if and only if $A^{**}$ has a $weak^* bounded approximate $$identity(=W^*BAI)$. If $A$ is Arens regular and $A$ \\noindent has a BAI, then $A^*$ factors on both sides. In this paper we introduce new concepts $LW^*W$ and $RW^*W$- property and we show that under certain conditions if $A$ has $LW^*W$ and $RW^*W$- property, then $A$ is Arens regular and also if $A$ is Arens regular, then $A$ has $LW^*W$ and $RW^*W$- property. We also offer some applications of these new concepts for the special algebras $l^1(G), L^1(G), M(G)$, and $A(G)$.", "revisions": [ { "version": "v1", "updated": "2009-04-27T07:43:28.000Z" } ], "analyses": { "subjects": [ "46L06", "46L07", "46L10", "47L25" ], "keywords": [ "banach algebra", "arens regularity", "second dual" ], "note": { "typesetting": "TeX", "pages": 15, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2009arXiv0904.4102H" } } }