On the James and von Neumann-Jordan constants in Banach spaces

Wang, Fenghui

doi:10.1090/S0002-9939-09-10107-7

On the James and von Neumann-Jordan constants in Banach spaces
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Proc. Amer. Math. Soc. 138 (2010), 695-701 Request permission

Abstract:

Recently Alonso, Martín and Papini conjectured that the value of the von Neumann-Jordan constant is less than or equal to that of the James constant. This paper presents an affirmative answer to such a conjecture. Moreover, we obtain a sharp estimate for the von Neumann-Jordan constant.

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