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A new proof of James' sup theorem

Marianne Morillon
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Abstract

We provide a new proof of James' sup theorem for (non necessarily separable) Banach spaces. One of the ingredients is the following generalization of a theorem of Hagler and Johnson (1977) : "If a normed space $E$ does not contain any asymptotically isometric copy of $\ell^1(\IN)$, then every bounded sequence of $E'$ has a normalized block sequence pointwise converging to 0".

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Marianne Morillon. 2005-05-10. A new proof of James' sup theorem. https://arxiv.org/abs/math/0505176

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