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arXiv · 2404.11430

Separating diameter two properties from their weak-star counterparts in spaces of Lipschitz functions

Rainis Haller·Jaan Kristjan Kaasik·Andre Ostrak
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Abstract

We address some open problems concerning Banach spaces of real-valued Lipschitz functions. Specifically, we prove that the diameter two properties differ from their weak-star counterparts in these spaces. In particular, we establish the existence of dual Banach spaces lacking the symmetric strong diameter two property but possessing its weak-star counterpart. We show that there exists an octahedral Lipschitz-free space whose bidual is not octahedral. Furthermore, we prove that the Banach space of real-valued Lipschitz functions from any infinite subset of $\ell_1$ possesses the symmetric strong diameter two property. These results are achieved by introducing new sufficient conditions, providing new examples and clarifying the status of known ones.

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Rainis Haller, Jaan Kristjan Kaasik, Andre Ostrak. 2024-04-17. Separating diameter two properties from their weak-star counterparts in spaces of Lipschitz functions. https://arxiv.org/abs/2404.11430

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