Title:
|
Subgroups of $\Bbb R$-factorizable groups (English) |
Author:
|
Hernández, Constancio |
Author:
|
Tkačenko, Michael |
Language:
|
English |
Journal:
|
Commentationes Mathematicae Universitatis Carolinae |
ISSN:
|
0010-2628 (print) |
ISSN:
|
1213-7243 (online) |
Volume:
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39 |
Issue:
|
2 |
Year:
|
1998 |
Pages:
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371-378 |
. |
Category:
|
math |
. |
Summary:
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The properties of $\Bbb R$-factorizable groups and their subgroups are studied. We show that a locally compact group $G$ is $\Bbb R$-factorizable if and only if $G$ is $\sigma$-compact. It is proved that a subgroup $H$ of an $\Bbb R$-factorizable group $G$ is $\Bbb R$-factorizable if and only if $H$ is $z$-embedded in $G$. Therefore, a subgroup of an $\Bbb R$-factorizable group need not be $\Bbb R$-factorizable, and we present a method for constructing non-$\Bbb R$-factorizable dense subgroups of a special class of $\Bbb R$-factorizable groups. Finally, we construct a closed $G_{\delta}$-subgroup of an $\Bbb R$-fac\-torizable group which is not $\Bbb R$-factorizable. (English) |
Keyword:
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$\Bbb R$-factorizable group |
Keyword:
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$z$-embedded set |
Keyword:
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$\aleph_0$-bounded group |
Keyword:
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$P$-group |
Keyword:
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Lindelöf group |
MSC:
|
22A05 |
MSC:
|
22D05 |
MSC:
|
54C50 |
MSC:
|
54H11 |
idZBL:
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Zbl 1100.54026 |
idMR:
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MR1651979 |
. |
Date available:
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2009-01-08T18:41:12Z |
Last updated:
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2012-04-30 |
Stable URL:
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http://hdl.handle.net/10338.dmlcz/119014 |
. |
Reference:
|
[1] Comfort W.W.: Compactness like properties for generalized weak topological sums.Pacific J. Math. 60 (1975), 31-37. Zbl 0307.54016, MR 0431088 |
Reference:
|
[2] Comfort W.W., Ross K.A.: Pseudocompactness and uniform continuity in topological groups.Pacific J. Math. 16 (1966), 483-496. Zbl 0214.28502, MR 0207886 |
Reference:
|
[3] Guran I.I.: On topological groups close to being Lindelöf.Soviet Math. Dokl. 23 (1981), 173-175. Zbl 0478.22002 |
Reference:
|
[4] Hernández S., Sanchiz M., Tkačenko M.: Bounded sets in spaces and topological groups.submitted for publication. |
Reference:
|
[5] Engelking R.: General Topology.Heldermann Verlag, 1989. Zbl 0684.54001, MR 1039321 |
Reference:
|
[6] Pontryagin L.S.: Continuous Groups.Princeton Univ. Press, Princeton, 1939. Zbl 0659.22001 |
Reference:
|
[7] Tkačenko M.G.: Subgroups, quotient groups and products of $\Bbb R$-factorizable groups.Topology Proceedings 16 (1991), 201-231. MR 1206464 |
Reference:
|
[8] Tkačenko M.G.: Factorization theorems for topological groups and their applications.Topology Appl. 38 (1991), 21-37. MR 1093863 |
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