Open Access

A pythagorean approach in Banach spaces

Journal of Inequalities and Applications20062006:94982

https://doi.org/10.1155/JIA/2006/94982

Received: 30 December 2003

Accepted: 4 May 2004

Published: 3 January 2006

Abstract

Let be a Banach space and let be the unit sphere of . Parameters , , , and , where and are introduced and studied. The values of these parameters in the spaces and function spaces are estimated. Among the other results, we proved that a Banach space with , or is uniform nonsquare; and a Banach space with , or has uniform normal structure.

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Authors’ Affiliations

(1)
Department of Mathematics, Community College of Philadelphia

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Copyright

© Gao 2006

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.