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Nearly metacompact spaces - MaRDI portal

Nearly metacompact spaces (Q1807579)

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scientific article; zbMATH DE number 1367561
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Nearly metacompact spaces
scientific article; zbMATH DE number 1367561

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    Nearly metacompact spaces (English)
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    9 May 2000
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    A space \(X\) is called nearly metacompact (resp. nearly meta-Lindelöf) provided that for every open cover \({\mathcal U}\) of \(X\) there is an open refinement \({\mathcal V}\) which is point-finite (resp. point-countable) on a dense subset of \(X\). The authors give many results and examples regarding these properties. For example, they show that every countably compact, nearly meta-Lindelöf \(T_3\)-space is compact, and they provide an example to show that this result fails for spaces which are only \(T_2\). They show that nearly metacompact spaces which are Fréchet (or radial, or lob) are meta-Lindelöf. They show that every space can be embedded as a closed subspace of a nearly metacompact space (a characteristic shared by the irreducible spaces), and they construct a nearly metacompact \(T_2\)-space which is not irreducible. It is a question whether such a space can be constructed to be regular.
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    meta-Lindelöf
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