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Keywords:
hyperspaces; Vietoris topology; locally finite topology; Hausdorff metric; compactness; normality; countable compactness
hyperspaces; Vietoris topology; locally finite topology; Hausdorff metric; compactness; normality; countable compactness
Summary:
One of the most celebrated results in the theory of hyperspaces says that if the Vietoris topology on the family of all nonempty closed subsets of a given space is normal, then the space is compact (Ivanova-Keesling-Velichko). The known proofs use cardinality arguments and are long. In this paper we present a short proof using known results concerning Hausdorff uniformities.
References:
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