ArticleOriginal scientific text

Title

When are Borel functions Baire functions?

Authors 1

Affiliations

  1. Cowiconsult, Consulting Engineers and Planners AS, 15, Parallelvej, Dk-2800 Lyngby, Denmark

Abstract

The following two theorems give the flavour of what will be proved. Theorem. Let Y be a complete metric space. Then the families of first Baire class functions and of first Borel class functions from [0,1] to Y coincide if and only if Y is connected and locally connected.} Theorem. Let Y be a separable metric space. Then the families of second Baire class functions and of second Borel class functions from [0,1] to Y coincide if and only if for all finite sequences U1,...,Uq of nonempty open subsets of Y there exists a continuous function ϕ:[0,1] → Y such that ϕ-1(Ui)Ø for all i ≤ q.

Bibliography

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Additional information

http://matwbn.icm.edu.pl/ksiazki/fm/fm143/fm14324.pdf

Pages:
137-152
Main language of publication
English
Received
1992-09-07
Accepted
1993-02-15
Published
1993
Exact and natural sciences