Title:
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Convergence in compacta and linear Lindelöfness (English) |
Author:
|
Arhangel'skii, A. V. |
Author:
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Buzyakova, R. Z. |
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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39 |
Issue:
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1 |
Year:
|
1998 |
Pages:
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159-166 |
. |
Category:
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math |
. |
Summary:
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Let $X$ be a compact Hausdorff space with a point $x$ such that $X\setminus \{ x\}$ is linearly Lindelöf. Is then $X$ first countable at $x$? What if this is true for every $x$ in $X$? We consider these and some related questions, and obtain partial answers; in particular, we prove that the answer to the second question is ``yes'' when $X$ is, in addition, $\omega $-monolithic. We also prove that if $X$ is compact, Hausdorff, and $X\setminus \{ x\}$ is strongly discretely Lindelöf, for every $x$ in $X$, then $X$ is first countable. An example of linearly Lindelöf hereditarily realcompact non-Lindelöf space is constructed. Some intriguing open problems are formulated. (English) |
Keyword:
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point of complete accumulation |
Keyword:
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linearly Lindelöf space |
Keyword:
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local compactness |
Keyword:
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first countability |
Keyword:
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$\kappa $-accessible diagonal |
MSC:
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54A25 |
MSC:
|
54D30 |
MSC:
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54E35 |
MSC:
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54F99 |
idZBL:
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Zbl 0937.54022 |
idMR:
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MR1623006 |
. |
Date available:
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2009-01-08T18:39:45Z |
Last updated:
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2012-04-30 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/118994 |
. |
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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