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arXiv · 1301.6250

A Bohl-Bohr-Kadets type theorem characterizing Banach spaces not containing c0

Bálint Farkas
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Abstract

We prove that a separable Banach space $E$ does not contain a copy of the space $\co$ of null-sequences if and only if for every doubly power-bounded operator $T$ on $E$ and for every vector $x\in E$ the relative compactness of the sets $\{T^{n+m}x-T^nx: n\in \NN\}$ (for some/all $m\in\NN$, $m\geq 1$) and $\{T^nx:n\in \NN\}$ are equivalent. With the help of the Jacobs--de Leeuw--Glicksberg decomposition of strongly compact semigroups the case of (not necessarily invertible) power-bounded operators is also handled.

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Bálint Farkas. 2013-01-26. A Bohl-Bohr-Kadets type theorem characterizing Banach spaces not containing c0. https://arxiv.org/abs/1301.6250

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