On the topologies of a hyperspace of a metrizable topological space
Abstract
The properties of the topology $\tau_{inf}$, which is the infimum of the set of all topologies generated by the Hausdorff metrics on the hyperspace $\exp X$ of a metrizable topological space $X$ are studied. As one of the main results necessary and sufficient conditions for the metrizability (with Hausdorff metric) of $\tau_{inf}$ are obtained. We also show that $\exp X$ with the topology $\tau_{inf}$ is first-countable space if and only if a space $X$ is locally compact and second-countable. Besides we investigate relations between $\tau_{inf}$ and other topologies on the $\exp X$: Vietoris topology, Fell topology and locally finite topology.
About the Authors
A. S. BedritskiyBelarus
V. L. Timokhovich
Belarus
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Review
For citations:
Bedritskiy A.S., Timokhovich V.L. On the topologies of a hyperspace of a metrizable topological space. Trudy Instituta matematiki. 2023;31(2):15-27. (In Russ.)