The von Neumann-Jordan constant, weak orthogonality and normal structure in Banach spaces

Jiménez-Melado, Antonio; Llorens-Fuster, Enrique; Saejung, Satit

doi:10.1090/S0002-9939-05-08362-0

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.

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