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Constructive complements of unions of two closed sets

✍ Scribed by Douglas S. Bridges

Publisher
John Wiley and Sons
Year
2004
Tongue
English
Weight
69 KB
Volume
50
Category
Article
ISSN
0044-3050

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✦ Synopsis

Abstract

It is well known that in Bishop‐style constructive mathematics, the closure of the union of two subsets of ℝ is β€˜not’ the union of their closures. The dual situation, involving the complement of the closure of the union, is investigated constructively, using completeness of the ambient space in order to avoid any application of Markov's Principle. (Β© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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