Title:
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Pointwise convergence and the Wadge hierarchy (English) |
Author:
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Andretta, Alessandro |
Author:
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Marcone, Alberto |
Language:
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English |
Journal:
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Commentationes Mathematicae Universitatis Carolinae |
ISSN:
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0010-2628 (print) |
ISSN:
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1213-7243 (online) |
Volume:
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42 |
Issue:
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1 |
Year:
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2001 |
Pages:
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159-172 |
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Category:
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math |
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Summary:
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We show that if $X$ is a $\Sigma _1^1$ separable metrizable space which is not $\sigma $-compact then $C_p^* (X)$, the space of bounded real-valued continuous functions on $X$ with the topology of pointwise convergence, is Borel-$\Pi _1^1$-complete. Assuming projective determinacy we show that if $X$ is projective not $\sigma $-compact and $n$ is least such that $X$ is $\Sigma _n^1$ then $C_p (X)$, the space of real-valued continuous functions on $X$ with the topology of pointwise convergence, is Borel-$\Pi _n^1$-complete. We also prove a simultaneous improvement of theorems of Christensen and Kechris regarding the complexity of a subset of the hyperspace of the closed sets of a Polish space. (English) |
Keyword:
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Wadge hierarchy |
Keyword:
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function spaces |
Keyword:
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pointwise convergence |
MSC:
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03E15 |
MSC:
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28A05 |
MSC:
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54C35 |
MSC:
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54H05 |
idZBL:
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Zbl 1052.03023 |
idMR:
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MR1825380 |
. |
Date available:
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2009-01-08T19:08:58Z |
Last updated:
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2012-04-30 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/119231 |
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Reference:
|
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Reference:
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Reference:
|
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Reference:
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Reference:
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Reference:
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Reference:
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Reference:
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Reference:
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Reference:
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Reference:
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