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arXiv · 2111.10122

Two new examples of Banach spaces with a plastic unit ball

Rainis Haller·Nikita Leo·Olesia Zavarzina
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Abstract

We prove that Banach spaces $\ell_1\oplus_2\mathbb{R}$ and $X\oplus_\infty Y$, with strictly convex $X$ and $Y$, have plastic unit balls (we call a metric space plastic if every non-expansive bijection from this space onto itself is an isometry).

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Rainis Haller, Nikita Leo, Olesia Zavarzina. 2021-11-19. Two new examples of Banach spaces with a plastic unit ball. https://arxiv.org/abs/2111.10122

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