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Two countable Hausdorff almost regular spaces every continuous map of which into every Urysohn space is constant - MaRDI portal

Two countable Hausdorff almost regular spaces every continuous map of which into every Urysohn space is constant (Q1187070)

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scientific article; zbMATH DE number 38594
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Two countable Hausdorff almost regular spaces every continuous map of which into every Urysohn space is constant
scientific article; zbMATH DE number 38594

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    Two countable Hausdorff almost regular spaces every continuous map of which into every Urysohn space is constant (English)
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    28 June 1992
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    Summary: We construct two countable, Hausdorff, almost regular spaces \(I(S)\), \(I(T)\) having the following properties: (1) Every continuous map of \(I(S)\) (resp. \(I(T)\)) into every Urysohn space is constant (hence, both spaces ar connected). (2) For every point of \(I(S)\) (resp. of \(I(T)\)) and for every open neighborhood \(U\) of this point there exists an open neighbourhood \(V\) of it such that \(V\subseteq U\) and every continuous map of \(V\) into every Urysohn space is constant (hence both spaces are locally connected). (3) The space \(I(S)\) is first countable and the space \(I(T)\) nowhere first countable. A consequence of the above is the construction of two countable, (connected) Hausdorff, almost regular spaces with a dispersion point and similar properties. Unfortunately, none of these spaces is Urysohn.
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    almost regular spaces
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    Urysohn space
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    dispersion point
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