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ON A PROBLEM OF TALAGRAND CONCERNING SEPARATELY CONTINUOUS FUNCTIONS

Published online by Cambridge University Press:  06 February 2020

Volodymyr Mykhaylyuk
Affiliation:
Jan Kochanowski University in Kielce, Poland Yurii Fedkovych Chernivtsi National University, Ukraine ([email protected])
Roman Pol
Affiliation:
University of Warsaw, Poland ([email protected])

Abstract

We construct a separately continuous function $e:E\times K\rightarrow \{0,1\}$ on the product of a Baire space $E$ and a compact space $K$ such that no restriction of $e$ to any non-meagre Borel set in $E\times K$ is continuous. The function $e$ has no points of joint continuity, and, hence, it provides a negative solution of Talagrand’s problem in Talagrand [Espaces de Baire et espaces de Namioka, Math. Ann.270 (1985), 159–164].

Type
Research Article
Copyright
© Cambridge University Press 2020

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