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Compactifications and A-compactifications of frames. Proximal frames

Published online by Cambridge University Press:  24 October 2008

Georgi D. Dimov
Affiliation:
Department of Mathematics and Computer Science, University ofSofia, Blvd. J. Bourchier 5.1126 Sofia, Bulgaria
Gino Tironi
Affiliation:
Department of Mathematical Sciences, University of Trieste, P.le Europa 1, 34100 Trieste, Italy

Extract

The aim of this paper is to give two new descriptions of the ordered set of all (up to equivalence) regular compactifications of a completely regular frame. F and to introduce and study the notion of A-frame as a generalization of the notion of Alexandroff space (known also as zero-set space) (Alexandroff[l], Gordon[15]). A description of the ordered set of all (up to equivalence) A-compactifications of an A-frame by means of an ordered by inclusion set of some distributive lattices (called AP-sublattices) is obtained. It implies that any A-frame has a greatest A-compactification and leads to the descriptions of A new category isomorphic to the category of proximal frames is introduced. A question for compactifications of frames analogous to the R. Chandler's question [8, p. 71] for compactifications of spaces is formulated and solved. Many results of [1], [3], [15], [23], [9], [10] and [11] are generalized.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1996

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