{ "id": "1811.02393", "version": "v1", "published": "2018-11-06T15:03:55.000Z", "updated": "2018-11-06T15:03:55.000Z", "title": "Left ideals of Banach algebras and dual Banach algebras", "authors": [ "Jared T. White" ], "comment": "20 pages", "categories": [ "math.FA" ], "abstract": "We define what it means for a Banach algebra to be topologically left Noetherian. We show that if $G$ is a compact group, then $L^{\\, 1}(G)$ is topologically left Noetherian if and only if $G$ is metrisable. We prove that given a Banach space $E$ such that $E'$ has BAP, the algebra of compact operators $\\mathcal{K}(E)$ is topologically left Noetherian if and only if $E'$ is separable; it is topologically right Noetherian if and only if $E$ is separable. We then define what it means for a dual Banach algebra to be weak*-topologically left Noetherian, and give some examples for which this condition holds. Finally we give a unified approach to classifying the weak*-closed left ideals of certain dual Banach algebras that are also multiplier algebras, with applications to $M(G)$ for $G$ a compact group, and $\\mathcal{B}(E)$ for $E$ a reflexive Banach space with AP.", "revisions": [ { "version": "v1", "updated": "2018-11-06T15:03:55.000Z" } ], "analyses": { "subjects": [ "16P40", "46H10", "43A10", "43A20", "47L10" ], "keywords": [ "dual banach algebra", "left ideals", "topologically left noetherian", "compact group", "banach space" ], "note": { "typesetting": "TeX", "pages": 20, "language": "en", "license": "arXiv", "status": "editable" } } }