Title: | A countably cellular topological group all of whose countable subsets are closed need not be $\mathbb{R}$-factorizable (English) |
Author: | Tkachenko, Mikhail |
Language: | English |
Journal: | Commentationes Mathematicae Universitatis Carolinae |
ISSN: | 0010-2628 (print) |
ISSN: | 1213-7243 (online) |
Volume: | 64 |
Issue: | 1 |
Year: | 2023 |
Pages: | 127-135 |
Summary lang: | English |
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Category: | math |
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Summary: | We construct a Hausdorff topological group $G$ such that $\aleph_1$ is a precalibre of $G$ (hence, $G$ has countable cellularity), all countable subsets of $G$ are closed and $C$-embedded in $G$, but $G$ is not $\mathbb{R}$-factorizable. This solves Problem 8.6.3 from the book ``Topological Groups and Related Structures" (2008) in the negative. (English) |
Keyword: | $\mathbb{R}$-factorizable |
Keyword: | cellularity |
Keyword: | $C$-embedded |
Keyword: | Sorgenfrey line |
Keyword: | $P$-group |
Keyword: | Dieudonné completion |
Keyword: | Hewitt--Nachbin completion |
Keyword: | Bohr topology |
MSC: | 22A05 |
MSC: | 54D30 |
MSC: | 54G20 |
MSC: | 54H11 |
idZBL: | Zbl 07790587 |
idMR: | MR4631595 |
DOI: | 10.14712/1213-7243.2023.016 |
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Date available: | 2023-08-28T09:52:12Z |
Last updated: | 2024-02-13 |
Stable URL: | http://hdl.handle.net/10338.dmlcz/151801 |
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