Powered by OpenAIRE graph
Found an issue? Give us feedback
image/svg+xml Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Closed Access logo, derived from PLoS Open Access logo. This version with transparent background. http://commons.wikimedia.org/wiki/File:Closed_Access_logo_transparent.svg Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao zbMATH Openarrow_drop_down
image/svg+xml Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao Closed Access logo, derived from PLoS Open Access logo. This version with transparent background. http://commons.wikimedia.org/wiki/File:Closed_Access_logo_transparent.svg Jakob Voss, based on art designer at PLoS, modified by Wikipedia users Nina and Beao
zbMATH Open
Article . 2002
Data sources: zbMATH Open
The Quarterly Journal of Mathematics
Article . 2002 . Peer-reviewed
Data sources: Crossref
versions View all 2 versions
addClaim

A Constructive Uniform Continuity Theorem

A constructive uniform continuity theorem
Authors: Ishihara, Hajime; Schuster, Peter;

A Constructive Uniform Continuity Theorem

Abstract

The celebrated uniform continuity theorem of classical mathematics states that a pointwise continuous function with metric domain is uniformly continuous if that domain is compact (which, for the purposes of constructive mathematics, is taken to mean totally bounded and complete). While the theorem remains valid within the framework of intuitionistic mathematics strengthened by the principle of continuous choice, it is known to fail in weaker constructive systems (e.g., Markov-style recursive mathematics). In hopes of redressing this difficulty, the authors of the present paper prove, within the confines of intuitionistic logic enriched with the principle of dependent choice, the following constructive uniform continuity theorem: A strongly continuous function with metric domain is uniformlv continuous if that domain is totally bounded (not necessarily complete). [What strong continuity means in the present context is explained as follows. Given a metric space \((X,d)\), define two subsets \(A\) and \(B\) of \(X\) to be apart if there is some positive real number \(r\) such that \(d(a,b)\geq r\) for all \(a\in A\) and \(b\in B\). A function \(f:X\to Y\) between metric spaces is then strongly continuous if \(A\) and \(B\) are apart in \(X\) whenever the images \(f[A]\) and \(f[B]\) are apart in \(Y]\).

Keywords

constructive mathematics, Continuous maps, intuitionistic logic, Other constructive mathematics, dependent choice

  • BIP!
    Impact byBIP!
    selected citations
    These citations are derived from selected sources.
    This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    5
    popularity
    This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
    Average
    influence
    This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
    Top 10%
    impulse
    This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
    Top 10%
Powered by OpenAIRE graph
Found an issue? Give us feedback
selected citations
These citations are derived from selected sources.
This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Citations provided by BIP!
popularity
This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.
BIP!Popularity provided by BIP!
influence
This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).
BIP!Influence provided by BIP!
impulse
This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.
BIP!Impulse provided by BIP!
5
Average
Top 10%
Top 10%
Upload OA version
Are you the author of this publication? Upload your Open Access version to Zenodo!
It’s fast and easy, just two clicks!