{ "id": "0708.4029", "version": "v1", "published": "2007-08-29T21:47:56.000Z", "updated": "2007-08-29T21:47:56.000Z", "title": "Ultrapowers of Banach algebras and modules", "authors": [ "Matthew Daws" ], "comment": "17 pages", "journal": "Glasg. Math. J. 50 (2008), no. 3, 539--555.", "categories": [ "math.FA" ], "abstract": "The Arens products are the standard way of extending the product from a Banach algebra $\\mc A$ to its bidual $\\mc A''$. Ultrapowers provide another method which is more symmetric, but one that in general will only give a bilinear map, which may not be associative. We show that if $\\mc A$ is Arens regular, then there is at least one way to use an ultrapower to recover the Arens product, a result previously known for C$^*$-algebras. Our main tool is a Principle of Local Reflexivity result for modules and algebras.", "revisions": [ { "version": "v1", "updated": "2007-08-29T21:47:56.000Z" } ], "analyses": { "subjects": [ "46B07", "46B08", "46H05", "46H25", "46L05" ], "keywords": [ "banach algebra", "ultrapower", "arens product", "local reflexivity result", "main tool" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 17, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2007arXiv0708.4029D" } } }