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

Wang, Fenghui

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

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ISSN 1088-6826(online) ISSN 0002-9939(print)

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

Author: Fenghui Wang
Journal: Proc. Amer. Math. Soc. 138 (2010), 695-701
MSC (2000): Primary 46B20
Posted: October 7, 2009
MathSciNet review: 2557186
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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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