A Hahn-Banach Theorem in Subbase Convexity Theory

Vel, M. van de

Canadian journal of mathematics, Tome 32 (1980) no. 4, pp. 804-820

Résumé

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].

Détail

DOI : 10.4153/CJM-1980-061-x

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