{ "id": "1803.04672", "version": "v1", "published": "2018-03-13T08:05:47.000Z", "updated": "2018-03-13T08:05:47.000Z", "title": "On closed non-vanishing ideals in $C_B(X)$ II; compactness properties", "authors": [ "A. Khademi", "M. R. Koushesh" ], "comment": "12 pages", "categories": [ "math.FA" ], "abstract": "For a completely regular space $X$, let $C_B(X)$ be the normed algebra of all bounded continuous scalar-valued mappings on $X$ equipped with pointwise addition and multiplication and the supremum norm and let $C_0(X)$ be its subalgebra consisting of mappings vanishing at infinity. For a non-vanishing closed ideal $H$ of $C_B(X)$ we study properties of its spectrum $\\mathfrak{sp}(H)$ which may be characterized as the unique locally compact (Hausdorff) space $Y$ such that $H$ and $C_0(Y)$ are isometrically isomorphic. We concentrate on compactness properties of $\\mathfrak{sp}(H)$ and find necessary and sufficient (algebraic) conditions on $H$ such that the spectrum $\\mathfrak{sp}(H)$ satisfies (topological) properties such as the Lindel\\\"{o}f property, $\\sigma$-compactness, countable compactness, pseudocompactness and paracompactness.", "revisions": [ { "version": "v1", "updated": "2018-03-13T08:05:47.000Z" } ], "analyses": { "keywords": [ "compactness properties", "closed non-vanishing ideals", "supremum norm", "regular space", "study properties" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable" } } }