{ "id": "2307.09167", "version": "v1", "published": "2023-07-18T11:43:16.000Z", "updated": "2023-07-18T11:43:16.000Z", "title": "On linearisation, existence and uniqueness of preduals", "authors": [ "Karsten Kruse" ], "categories": [ "math.FA" ], "abstract": "We study the problem of existence and uniqueness of preduals of locally convex Hausdorff spaces. We derive necessary and sufficient conditions for the existence of a predual with certain properties of a bornological locally convex Hausdorff space $X$. Then we turn to the case that $X=\\mathcal{F}(\\Omega)$ is a space of scalar-valued functions on a non-empty set $\\Omega$ and characterise those among them which admit a special predual, namely a strong linearisation, i.e. there is a locally convex Hausdorff space $Y$, a map $\\delta\\colon\\Omega\\to Y$ and a topological isomorphism $T\\colon\\mathcal{F}(\\Omega)\\to Y_{b}'$ such that $T(f)\\circ \\delta= f$ for all $f\\in\\mathcal{F}(\\Omega)$. We also lift such a linearisation to the case of vector-valued functions, covering many previous results on linearisations, and use it to characterise the bornological spaces $\\mathcal{F}(\\Omega)$ with (strongly) unique predual in certain classes of locally convex Hausdorff spaces.", "revisions": [ { "version": "v1", "updated": "2023-07-18T11:43:16.000Z" } ], "analyses": { "subjects": [ "46A08", "46A20", "46A70", "46B10", "46E10", "46E40" ], "keywords": [ "uniqueness", "bornological locally convex hausdorff space", "unique predual", "sufficient conditions", "non-empty set" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }