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Normality and countable paracompactness of hyperspaces of ordinals - MaRDI portal

Normality and countable paracompactness of hyperspaces of ordinals (Q864449)

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scientific article; zbMATH DE number 5123618
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Normality and countable paracompactness of hyperspaces of ordinals
scientific article; zbMATH DE number 5123618

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    Normality and countable paracompactness of hyperspaces of ordinals (English)
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    9 February 2007
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    For a space \(X\), \(2^X\) denotes the space consisting of all nonempty closed subsets of \(X\) with the Vietoris topology and \({\mathcal K}(X)\) denotes the subspace of \(2^X\) consisting of all compact subsets of \(X\). The author discusses normality and countable paracompactness of hyperspaces of ordinals and proves the following results: Theorem 5. \({\mathcal K}(\alpha)\) is countably paracompact for all nonzero-ordinals \(\alpha\). Theorem 8. If \(\kappa\) is a regular uncountable cardinal, then \({\mathcal K}(\kappa)\) is normal. The author also discusses the space \(2^X\).
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    normal
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    countably paracompact
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    hyperspace
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    ordinal
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    elementary submodel
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