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Uniform Spaces as Nice Images of Nice Uniform and Metric Spaces(1)

Published online by Cambridge University Press:  20 November 2018

Richard Willmott*
Affiliation:
Department of Mathematics Queen's University, Kingston, Ontario K7L 3N6
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The classical theorem that a complete separable metric space is the image under a one-to-one continuous function of a closed subset of the irrational numbers has been extended in two directions, the first leading to various characterizations in descriptive set theory of Borel and analytic sets or generalizations of them as continuous images of certain subsets of the irrationals, or generalizations of them (see, e.g. [3] and references cited there; [4]; [6]). The second direction originates in the observation that a closed subset of the irrationals is a complete 0-dimensional metric space (under a suitable metric), and leads to the general question asked by Alexandroff [1], "Which spaces can be represented as images of 'nice' (e.g. metric, 0-dimensional) spaces under 'nice' [e.g. one-to-one, open, closed, perfect] continuous mappings?" (See, e.g. [7], [9] and the survey articles [1], [2] and [11].)

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1980

Footnotes

(1)

This work was supported by the National Research Council of Canada.

References

1. Alexandroff, P., On some results concerning topological spaces and their continuous mappings, General Topology and its Relations to Modern Analysis and Algebra, Proc. Prague Sympos. 1961, 41-54, Academia, Prague, 1962.Google Scholar
2. Arkhangel'skii, A. V., Mappings and Spaces, Uspehi Mat. Nauk 21 (1966), no. 4 (130), 133-184; Russian Math. Surveys 21 (1966), no. 4, 115-162.Google Scholar
3. Bressler, D. W. and Sion, M., The current theory of analytic sets, Canad. J. Math. 16 (1964), 207-230.Google Scholar
4. Engelking, R., Outline of general topology, North-Holland, Amsterdam, 1968.Google Scholar
5. Kelley, J. L., General topology, Van Nostrand, Princeton, 1959.Google Scholar
6. Kruse, Arthur H., Souslinoid and analytic sets in a general setting, Amer. Math. Soc. Memoir no. 86, 1969.Google Scholar
7. Michael, E., Representing spaces as images of metrizable and related spaces, Gen. Top. Appl. 1 (1971) 329-344.Google Scholar
8. Donald Monk, J., Introduction to set theory, McGraw-Hill, New York, 1969.Google Scholar
9. Ponomarev, V., Metric spaces and the continuous mappings connected with them, Dokl. Akad. Nauk SSSR 153 (1963), 1013-1016; Soviet Math. Dokl. 4 (1963), 1777-1780.Google Scholar
10. Ponomarev, V., Normal spaces as images of zero-dimensional ones, Dokl. Akad. Nauk SSSR 132 (1960), 1269-1272; Soviet Math. Dokl. 1 (1960), 774-776.Google Scholar
11. Rishel, T. W., Nice spaces, nice maps, General Topology and its Relations to Modern Analysis and Algebra, III. Proc. Third Prague Topological Sympos. 1971, 375-383, Academia, Prague, 1972Google Scholar
12. Rogers, C. A., Descriptive Borel sets, Proc. Royal Soc, A, 286 (1965), 455-478.Google Scholar
13. Steiner, A. K. and Steiner, E. F., The natural topology on the space AB, J. Math. Anal. App. 19 (1967), 174-178.Google Scholar
14. Stone, A. H., Non-separable Borel sets, Rozprawy Matematyczne 28, Warsaw, 1962.Google Scholar