{ "id": "2304.03455", "version": "v1", "published": "2023-04-07T03:03:11.000Z", "updated": "2023-04-07T03:03:11.000Z", "title": "The quasi-metrizability of hyperspaces", "authors": [ "Chuan Liu", "Fucai Lin" ], "comment": "11 pages", "categories": [ "math.GN" ], "abstract": "For a space $X$, let $(CL(X), \\tau_V)$, $(CL(X), \\tau_{locfin})$ and $(CL(X), \\tau_F)$ be the set $CL(X)$ of all nonempty closed subsets of $X$ which are endowed with Vietoris topology, locally finite topology and Fell topology respectively. We prove that $(CL(X), \\tau_V)$ is quasi-metrizable if and only if $X$ is a separable metrizable space and the set of all non-isolated points of $X$ is compact, $(CL(X), \\tau_{locfin})$ is quasi-metrizable or symmetrizable if and only if $X$ is metrizable and the set of all non-isolated points of $X$ is compact, and $(CL(X), \\tau_F)$ is quasi-metrizable if and only if $X$ is hemicompact and metrizable. As an application, we give a negative answer to a Conjecture in \\cite{LL2022}.", "revisions": [ { "version": "v1", "updated": "2023-04-07T03:03:11.000Z" } ], "analyses": { "subjects": [ "54B20", "54E35", "54E45" ], "keywords": [ "quasi-metrizability", "hyperspaces", "non-isolated points", "nonempty closed subsets", "fell topology" ], "note": { "typesetting": "TeX", "pages": 11, "language": "en", "license": "arXiv", "status": "editable" } } }