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An Ultrafilter Completion of a Nearness Space

Published online by Cambridge University Press:  20 November 2018

John W. Carlson*
Affiliation:
Mathematics Department, Emporia State University, Emporia, Kansas 66801, U.S.A.
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Abstract

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An ultrafilter completion is constructed for a nearness space. It is shown to preserve the Tl separation axiom. Characterizing conditions are given for it to be topological or for its topology to be compact. It is shown to have the simple extension topology and for a given Hausdorff space a compatible nearness structure is found for which its ultrafilter completion is homeomorphic to the Katetov H-closed extension.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1981

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