Sharper changes in topologies

Author:
Greg Hjorth

Journal:
Proc. Amer. Math. Soc. **127** (1999), 271-278

MSC (1991):
Primary 04A15

MathSciNet review:
1458878

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Abstract | References | Similar Articles | Additional Information

Abstract: Let be a Polish group, a Polish topology on a space , acting continuously on , with -invariant and in the Borel algebra generated by . Then there is a larger Polish topology on so that is open with respect to , still acts continuously on , *and* has a basis consisting of sets that are of the same Borel rank as relative to .

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Additional Information

**Greg Hjorth**

Affiliation:
Department of Mathematics, University of California Los Angeles, Los Angeles, California 90095-1555

Email:
greg@math.ucla.edu

DOI:
http://dx.doi.org/10.1090/S0002-9939-99-04498-6

Keywords:
Polish group,
topological group,
topology

Received by editor(s):
October 17, 1996

Received by editor(s) in revised form:
May 13, 1997

Communicated by:
Andreas R. Blass

Article copyright:
© Copyright 1999
American Mathematical Society