# Borel extensions of Baire measures

Fundamenta Mathematicae (1997)

- Volume: 154, Issue: 3, page 275-293
- ISSN: 0016-2736

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topAldaz, J.. "Borel extensions of Baire measures." Fundamenta Mathematicae 154.3 (1997): 275-293. <http://eudml.org/doc/212238>.

@article{Aldaz1997,

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.},

author = {Aldaz, J.},

journal = {Fundamenta Mathematicae},

keywords = {Mařík; quasi-Mařík; countably metacompact; Dowker; Baire measure; extension; metacompact space; Borel measure; Dowker space; Dowker-Mařík space},

language = {eng},

number = {3},

pages = {275-293},

title = {Borel extensions of Baire measures},

url = {http://eudml.org/doc/212238},

volume = {154},

year = {1997},

}

TY - JOUR

AU - Aldaz, J.

TI - Borel extensions of Baire measures

JO - Fundamenta Mathematicae

PY - 1997

VL - 154

IS - 3

SP - 275

EP - 293

AB - 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.

LA - eng

KW - Mařík; quasi-Mařík; countably metacompact; Dowker; Baire measure; extension; metacompact space; Borel measure; Dowker space; Dowker-Mařík space

UR - http://eudml.org/doc/212238

ER -

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