The topological structure of (homogeneous) spaces and groups with countable cs∗-character
In this paper we introduce and study three new cardinal topological invariants called the cs∗-, cs-, and sb-characters. The class of topological spaces with countable cs∗-character is closed under many topological operations and contains all N-spaces and all spaces with point-countable cs∗-network....
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Universitat Politècnica de València
2004-04-01
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doaj-7ee96f7213a14cffa41fdfdbbe4d351e2020-11-24T22:17:45ZengUniversitat Politècnica de ValènciaApplied General Topology1576-94021989-41472004-04-0151254810.4995/agt.2004.19931615The topological structure of (homogeneous) spaces and groups with countable cs∗-characterTaras Banak0Lubomyr Zdomskyi1Akademia SwietorzyskaIvan Franko Lviv National UniversityIn this paper we introduce and study three new cardinal topological invariants called the cs∗-, cs-, and sb-characters. The class of topological spaces with countable cs∗-character is closed under many topological operations and contains all N-spaces and all spaces with point-countable cs∗-network. Our principal result states that each non-metrizable sequential topological group with countable cs∗- character has countable pseudo-character and contains an open kω- subgroup. This result is specific for topological groups: under Martin Axiom there exists a sequential topologically homogeneous kω-space X with N0 = cs∗x (X) <ψ (X).http://polipapers.upv.es/index.php/AGT/article/view/1993sb-networkcs-networ, cs∗-networkSequential topological groupkω-groupTopologically homogeneous spaceSmall cardinalCardinal invariant |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Taras Banak Lubomyr Zdomskyi |
spellingShingle |
Taras Banak Lubomyr Zdomskyi The topological structure of (homogeneous) spaces and groups with countable cs∗-character Applied General Topology sb-network cs-networ , cs∗-network Sequential topological group kω-group Topologically homogeneous space Small cardinal Cardinal invariant |
author_facet |
Taras Banak Lubomyr Zdomskyi |
author_sort |
Taras Banak |
title |
The topological structure of (homogeneous) spaces and groups with countable cs∗-character |
title_short |
The topological structure of (homogeneous) spaces and groups with countable cs∗-character |
title_full |
The topological structure of (homogeneous) spaces and groups with countable cs∗-character |
title_fullStr |
The topological structure of (homogeneous) spaces and groups with countable cs∗-character |
title_full_unstemmed |
The topological structure of (homogeneous) spaces and groups with countable cs∗-character |
title_sort |
topological structure of (homogeneous) spaces and groups with countable cs∗-character |
publisher |
Universitat Politècnica de València |
series |
Applied General Topology |
issn |
1576-9402 1989-4147 |
publishDate |
2004-04-01 |
description |
In this paper we introduce and study three new cardinal topological invariants called the cs∗-, cs-, and sb-characters. The class of topological spaces with countable cs∗-character is closed under many topological operations and contains all N-spaces and all spaces with point-countable cs∗-network. Our principal result states that each non-metrizable sequential topological group with countable cs∗- character has countable pseudo-character and contains an open kω- subgroup. This result is specific for topological groups: under Martin Axiom there exists a sequential topologically homogeneous kω-space X with N0 = cs∗x (X) <ψ (X). |
topic |
sb-network cs-networ , cs∗-network Sequential topological group kω-group Topologically homogeneous space Small cardinal Cardinal invariant |
url |
http://polipapers.upv.es/index.php/AGT/article/view/1993 |
work_keys_str_mv |
AT tarasbanak thetopologicalstructureofhomogeneousspacesandgroupswithcountablecscharacter AT lubomyrzdomskyi thetopologicalstructureofhomogeneousspacesandgroupswithcountablecscharacter AT tarasbanak topologicalstructureofhomogeneousspacesandgroupswithcountablecscharacter AT lubomyrzdomskyi topologicalstructureofhomogeneousspacesandgroupswithcountablecscharacter |
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1725784674416984064 |