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arXiv · 1206.0654

Restricted Invertibility and the Banach-Mazur distance to the cube

Pierre Youssef
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Abstract

We prove a normalized version of the restricted invertibility principle obtained by Spielman-Srivastava. Applying this result, we get a new proof of the proportional Dvoretzky-Rogers factorization theorem recovering the best current estimate. As a consequence, we also recover the best known estimate for the Banach-Mazur distance to the cube: the distance of every n-dimensional normed space from \ell_{\infty}^n is at most (2n)^(5/6). Finally, using tools from the work of Batson-Spielman-Srivastava, we give a new proof for a theorem of Kashin-Tzafriri on the norm of restricted matrices.

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Pierre Youssef. 2012-06-04. Restricted Invertibility and the Banach-Mazur distance to the cube. https://doi.org/10.1112/s0025579313000144

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