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Discrete Sets and Discrete Maps

Published online by Cambridge University Press:  20 November 2018

Richard H. Warren*
Affiliation:
Department of Mathematics and Computer Science, University of Nebraska at Omaha, Omaha, Ne 68182
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Abstract

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A subset of a topological space is called discrete iff every point in the space has a neighborhood which meets the set in at most one point. Discrete sets are useful for decomposing the images of certain maps and for generalizing closed maps. All discrete sets are closed iff the space is T1. As a result of characterizing discrete and countably discrete maps, theorems due to Vaĭnšteĭn and Engelking are extended to these maps.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1982

References

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