ArticleOriginal scientific text
Title
Selections that characterize topological completeness
Authors 1, 2, 3
Affiliations
- Faculteit Wiskunde en Informatica, Vrije Universiteit, De Boelelaan 1081 A, 1081 HV Amsterdam, The Netherlands
- epartment of Mathematics, Warsaw University, Banacha 2, 00-913 Warszawa 59, Poland
- Institute of Mathematics, Academy of Sciences of the Czech Republic, Žitná 25, 11567 Praha 1, Czech Republic
Abstract
We show that the assertions of some fundamental selection theorems for lower-semicontinuous maps with completely metrizable range and metrizable domain actually characterize topological completeness of the target space. We also show that certain natural restrictions on the class of the domains change this situation. The results provide in particular answers to questions asked by Engelking, Heath and Michael [3] and Gutev, Nedev, Pelant and Valov [5].
Keywords
selection, Vietoris topology, completely metrizable
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