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arXiv · 2406.14104

The Extreme Points of the Unit Ball of the James space $J$ and its dual spaces

Spiros A. Argyros·Manuel González
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Abstract

We provide a new proof of S. Bellenot's characterization of the extreme points of the unit ball $B_J$ of James quasi-reflexive space $J$. We also provide an explicit description of the norm of $J^{**}$ which yields an analogous characterization for the extreme points of $B_{J^{**}}$. In the last part of the paper we describe the set of all extreme points of $B_{J^*}$ and its norm closure. It is remarkable that the descriptions of the extreme points of $B_J$ and $B_{J^*}$ are closely connected.

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Spiros A. Argyros, Manuel González. 2024-06-20. The Extreme Points of the Unit Ball of the James space $J$ and its dual spaces. https://arxiv.org/abs/2406.14104

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