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Towards the fixed point property for superreflexive spaces

Published online by Cambridge University Press:  17 April 2009

Andrzej Wiśnicki
Affiliation:
Department of Mathematics, Maria Curie -Sklodowska University, 20–031 Lublin, Poland e-mail: awisnic@golem.umcs.lublin.pl
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Abstract

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A Banach space X is said to have property (Sm) if every metrically convex set AX which lies on the unit sphere and has diameter not greater than one can be (weakly) separated from zero by a functional. We show that this geometrical condition is closely connected with the fixed point property for nonexpansive mappings in superreflexive spaces.

Type
Research Article
Copyright
Copyright © Australian Mathematical Society 2001

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