Perfect open and distinguishable multivalued maps
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- by Eric John Braude PDF
- Trans. Amer. Math. Soc. 182 (1973), 431-441 Request permission
Abstract:
It is shown that perfect open multivalued maps preserve $\mathcal {Z}$-analytic sets (which include compact zero sets) as well as other objects of descriptive set theory. The concept of “distinguishability", introduced by Frolík, is applied to multivalued maps, yielding a new class of such maps with similar preservation properties. That the projection of a compact zero set is a zero set is one corollary, and another is a generalized ${\mathcal {G}_\delta }$ diagonal metrization theorem.References
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Additional Information
- © Copyright 1973 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 182 (1973), 431-441
- MSC: Primary 54C50; Secondary 54H05
- DOI: https://doi.org/10.1090/S0002-9947-1973-0334137-0
- MathSciNet review: 0334137