On normal structure, fixed-point property and contractions of type $(\gamma )$
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- by M. A. Khamsi
- Proc. Amer. Math. Soc. 106 (1989), 995-1001
- DOI: https://doi.org/10.1090/S0002-9939-1989-0960647-6
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Abstract:
We prove that a Banach space $X$ has normal structure provided it contains a finite codimensional subspace $Y$ such that all spreading models for $Y$ have normal structure. We show that a Banach space $X$ is strictly convex if the set of fixed points of any nonexpansive map defined in any convex subset $C \subset X$ is convex and give a sufficient condition for uniform convexity of a space in terms of nonexpansive map of type $\left ( \gamma \right )$.References
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Bibliographic Information
- © Copyright 1989 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 106 (1989), 995-1001
- MSC: Primary 46B20; Secondary 47H10
- DOI: https://doi.org/10.1090/S0002-9939-1989-0960647-6
- MathSciNet review: 960647