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Geometry of Banach spaces and biorthogonal systems

S. J. Dilworth·Maria Girardi·W. B. Johnson
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Abstract

A separable Banach space X contains $\ell_1$ isomorphically if and only if X has a bounded wc_0^*-stable biorthogonal system. The dual of a separable Banach space X fails the Schur property if and only if X has a bounded wc_0^*-biorthogonal system.

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S. J. Dilworth, Maria Girardi, W. B. Johnson. 1999-11-20. Geometry of Banach spaces and biorthogonal systems. https://arxiv.org/abs/math/9911156

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