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arXiv · 0706.2483

An extension of a Bourgain--Lindenstrauss--Milman inequality

Omer Friedland·Sasha Sodin
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Abstract

Let || . || be a norm on R^n. Averaging || (\eps_1 x_1, ..., \eps_n x_n) || over all the 2^n choices of \eps = (\eps_1, ..., \eps_n) in {-1, +1}^n, we obtain an expression ||| . ||| which is an unconditional norm on R^n. Bourgain, Lindenstrauss and Milman showed that, for a certain (large) constant η> 1, one may average over (ηn) (random) choices of \eps and obtain a norm that is isomorphic to ||| . |||. We show that this is the case for any η> 1.

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Omer Friedland, Sasha Sodin. 2007-06-18. An extension of a Bourgain--Lindenstrauss--Milman inequality. https://arxiv.org/abs/0706.2483

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