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arXiv · 1806.00702

A new coarsely rigid class of Banach spaces

Florent Baudier·Gilles Lancien·Pavlos Motakis·Thomas Schlumprecht
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Abstract

We prove that the class of reflexive asymptotic-$c_0$ Banach spaces is coarsely rigid, meaning that if a Banach space $X$ coarsely embeds into a reflexive asymptotic-$c_0$ space $Y$, then $X$ is also reflexive and asymptotic-$c_0$. In order to achieve this result we provide a purely metric characterization of this class of Banach spaces. This metric characterization takes the form of a concentration inequality for Lipschitz maps on the Hamming graphs, which is rigid under coarse embeddings. Using an example of a quasi-reflexive asymptotic-$c_0$ space, we show that this concentration inequality is not equivalent to the non equi-coarse embeddability of the Hamming graphs.

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Florent Baudier, Gilles Lancien, Pavlos Motakis, Thomas Schlumprecht. 2020-04-13. A new coarsely rigid class of Banach spaces. https://doi.org/10.1017/s1474748019000732

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