RT Journal Article
T1 Movability and limits of polyhedra
A1 Fernández Laguna, Víctor
A1 Morón, Manuel A.
A1 Nhu, Nguyen Tho
A1 Rodríguez Sanjurjo, José Manuel
AB 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.
PB Polish acad sciences inst mathematics
SN 0016-2736
YR 1993
FD 1993
LK https://hdl.handle.net/20.500.14352/57334
UL https://hdl.handle.net/20.500.14352/57334
LA eng
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DS Docta Complutense
RD 30 abr 2024