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Movability and limits of polyhedra


Fernández Laguna, Víctor and Morón, Manuel A. and Nhu, Nguyen Tho and Rodríguez Sanjurjo, José Manuel (1993) Movability and limits of polyhedra. Fundamenta Mathematicae, 143 (3). pp. 191-201. ISSN 0016-2736

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We define a metric d(S), called the shape metric, on the hyperspace 2X of all non-empty compact subsets of a metric space X. Using it we prove that a compactum X in the Hilbert cube is movable if and only if X is the limit of a sequence of polyhedra in the shape metric. This fact is applied to show that the hyperspace (2R2, d(S)) is separable. On the other hand, we give an example showing that 2R2 is not separable in the fundamental metric introduced by Borsuk.

Item Type:Article
Uncontrolled Keywords:Shape metric; polyhedra; metric space
Subjects:Sciences > Mathematics > Topology
ID Code:15543

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Deposited On:08 Jun 2012 09:03
Last Modified:06 Feb 2014 10:26

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