English

Baire and weakly Namioka spaces

General Topology 2012-07-17 v1

Abstract

Recall that a Hausdorff space XX is said to be Namioka if for every compact (Hausdorff) space YY and every metric space ZZ, every separately continuous function f:X×YZf:X\times{Y}\rightarrow{Z} is continuous on D×YD\times{Y} for some dense GδG_\delta subset DD of XX. It is well known that in the class of all metrizable spaces, Namioka and Baire spaces coincide (Saint-Raymond, 1983). Further it is known that every completely regular Namioka space is Baire and that every separable Baire space is Namioka (Saint-Raymond, 1983). In our paper we study spaces XX, we call them weakly Namioka, for which the conclusion of the theorem for Namioka spaces holds provided that the assumption of compactness of YY is replaced by second countability of YY. We will prove that in the class of all completely regular separable spaces and in the class of all perfectly normal spaces, XX is Baire if and only if it is weakly Namioka.

Keywords

Cite

@article{arxiv.1207.3436,
  title  = {Baire and weakly Namioka spaces},
  author = {Zbigniew Piotrowski and Russell Waller},
  journal= {arXiv preprint arXiv:1207.3436},
  year   = {2012}
}

Comments

11 pages

R2 v1 2026-06-21T21:35:40.173Z