Abstract

We prove new existence results of fixed points for upper semicontinuous multi-valued maps with not necessarily convex values. We study two cases, according to whether the maps are defined on contractible spaces or on convex subsets of topological vector spaces possessing the simplicial approximation property

Author information

Contact details are reproduced from the original publication and may be historical.

Youcef Askoura

UFR Sciences Techniques, Lab. de Mathématiques, Université de Bretagne Occ., 6 Av. Victor Le Gorgeu, 29238 Brest, France
and: Laboratoire de Mathématiques CNRS-UMR 6205

askoura@univ-brest.fr

Christiane Godet-Thobie

UFR Sciences Techniques, Lab. de Mathématiques, Université de Bretagne Occ., 6 Av. Victor Le Gorgeu, 29238 Brest, France
and: Laboratoire de Mathématiques CNRS-UMR 6205

christiane.godet-thobie@univ-brest.fr

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Suggested citation

Y. Askoura, Ch. Godet-Thobie. “Fixed Points in Contractible Spaces and Convex Subsets of Topological Vector Spaces.” Journal of Convex Analysis 13 (2006), No. 2, 193–205. https://doi.org/10.68381/jca13021

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Published by Heldermann Verlag, 2006. Rights now held by Banach Press LLC.