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A Hahn-Banach Theorem in Subbase Convexity Theory

Published online by Cambridge University Press:  20 November 2018

M. van de Vel*
Affiliation:
Vrije Universiteit, Amsterdam, Holland
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In the last fifteen years, topology has shown up with an increasing interest in the use of closed subbases. Starting from Frink's internal characterization of complete regularity (Frink [6]), DeGroot and Aarts used closed subbases to obtain Hausdorff compactifications of completely regular spaces, thus giving a characterization of the latter in terms of their subbases [1]. The main tool of that paper is the notion of a linked system, which naturally leads to the notions of supercompactness and superextensions [7]. After 1970, these two topics developed to indepedennt theories, with several deep results available at this moment. Most results up to 1976 are summarized in [12].

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1980

References

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