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Selections generating new topologies - MaRDI portal

Selections generating new topologies (Q2454907)

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Selections generating new topologies
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    Selections generating new topologies (English)
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    22 October 2007
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    This paper considers some basic properties of continuous selections for the hyperspace of all non-empty subsets with at most two points in a Hausdorff and infinite topological space \(X\). Every such selection defines in a natural way an order-like relation on \(X\) and therefore also an interval-like topology on it. The main result shows that, for a second-countable zero-dimensional space \(X\), this topology may fail to be first-contable at some (or, even any) point of \(X\).
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    Hyperspace topology
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    Vietoris topology
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    continuous selection
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    weak selection
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