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Title

Borel extensions of Baire measures

Authors 1

Affiliations

  1. Departamento de Matemáticas, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain

Abstract

We show that in a countably metacompact space, if a Baire measure admits a Borel extension, then it admits a regular Borel extension. We also prove that under the special axiom ♣ there is a Dowker space which is quasi-Mařík but not Mařík, answering a question of H. Ohta and K. Tamano, and under P(c), that there is a Mařík Dowker space, answering a question of W. Adamski. We answer further questions of H. Ohta and K. Tamano by showing that the union of a Mařík space and a compact space is Mařík, that under "c is real-valued measurable", a Baire subset of a Mařík space need not be Mařík, and finally, that the preimage of a Mařík space under an open perfect map is Mařík.

Keywords

ENG
Mařík, quasi-Mařík, countably metacompact, Dowker

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Fundamenta Mathematicae
1997/154/3
Export to PBN, Opens in new tab
Pages:
275-293
Main language of publication
English
Received
1996-09-30
Published
1997
Exact and natural sciences