Open Access

Remarks on Separation of Convex Sets, Fixed-Point Theorem, and Applications in Theory of Linear Operators

Fixed Point Theory and Applications20072007:080987

DOI: 10.1155/2007/80987

Received: 20 February 2007

Accepted: 2 May 2007

Published: 5 July 2007

Abstract

Some properties of the linear continuous operator and separation of convex subsets are investigated in this paper and a dual space for a subspace of a reflexive Banach space with a strictly convex norm is constructed. Here also an existence theorem and fixed-point theorem for general mappings are obtained. Moreover, certain remarks on the problem of existence of invariant subspaces of a linear continuous operator are given.

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Authors’ Affiliations

(1)
Department of Mathematics, Faculty of Sciences, Hacettepe University

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Copyright

© Kamal N. Soltanov. 2007

This article is published under license to BioMed Central Ltd. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.