| Title:
|
Selections on $\Psi$-spaces (English) |
| Author:
|
Hrušák, M. |
| Author:
|
Szeptycki, P. J. |
| Author:
|
Tomita, A. H. |
| Language:
|
English |
| Journal:
|
Commentationes Mathematicae Universitatis Carolinae |
| ISSN:
|
0010-2628 (print) |
| ISSN:
|
1213-7243 (online) |
| Volume:
|
42 |
| Issue:
|
4 |
| Year:
|
2001 |
| Pages:
|
763-769 |
| . |
| Category:
|
math |
| . |
| Summary:
|
We show that if $\Cal A$ is an uncountable AD (almost disjoint) family of subsets of $\omega$ then the space $\Psi(\Cal A)$ does not admit a continuous selection; moreover, if $\Cal A$ is maximal then $\Psi(\Cal A)$ does not even admit a continuous selection on pairs, answering thus questions of T. Nogura. (English) |
| Keyword:
|
MAD family |
| Keyword:
|
Vietoris topology |
| Keyword:
|
continuous selection |
| MSC:
|
03E05 |
| MSC:
|
54B20 |
| MSC:
|
54C65 |
| idZBL:
|
Zbl 1090.54506 |
| idMR:
|
MR1883384 |
| . |
| Date available:
|
2009-01-08T19:18:39Z |
| Last updated:
|
2012-04-30 |
| Stable URL:
|
http://hdl.handle.net/10338.dmlcz/119291 |
| . |
| 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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| . |
