The von Neumann-Jordan constant, weak orthogonality and normal structure in Banach spaces
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- by Antonio Jiménez-Melado, Enrique Llorens-Fuster and Satit Saejung PDF
- Proc. Amer. Math. Soc. 134 (2006), 355-364 Request permission
Abstract:
We give some sufficient conditions for normal structure in terms of the von Neumann-Jordan constant, the James constant and the weak orthogonality coefficient introduced by B. Sims. In the rest of the paper, the von Neumann-Jordan constant and the James constant for the Bynum space $\ell _{2,\infty }$ are computed, and are used to show that our results are sharp.References
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Additional Information
- Antonio Jiménez-Melado
- Affiliation: Departamento de Análisis Matemático, Universidad de Málaga, Facultad de Ciencias, 29071 Málaga, Spain
- Email: melado@uma.es
- Enrique Llorens-Fuster
- Affiliation: Departamento de Análisis Matemático, Facultad de Matemáticas, 46100 Burjassot, Valencia, Spain
- Email: enrique.llorens@uv.es
- Satit Saejung
- Affiliation: Department of Mathematics, Khon Kaen University, Khon Kaen, 40002, Thailand
- Email: satitz@yahoo.com
- Received by editor(s): January 23, 2004
- Published electronically: September 21, 2005
- Communicated by: Jonathan M. Borwein
- © Copyright 2005 American Mathematical Society
- Journal: Proc. Amer. Math. Soc. 134 (2006), 355-364
- MSC (2000): Primary 46B20
- DOI: https://doi.org/10.1090/S0002-9939-05-08362-0
- MathSciNet review: 2176002