ArticleOriginal scientific text

Title

An isomorphic Dvoretzky's theorem for convex bodies

Authors 1, 2, 2

Affiliations

  1. Department of Mathematics, Technion, Haifa 32000, Israel
  2. Equipe d'Analyse, Université de Marne-la-Vallée, 2 rue de la Butte Verte, 93166 Noisy-le-Grand Cedex, France

Abstract

We prove that there exist constants C>0 and 0 < λ < 1 so that for all convex bodies K in n with non-empty interior and all integers k so that 1 ≤ k ≤ λn/ln(n+1), there exists a k-dimensional affine subspace Y of n satisfying d(YK,B2k)C(1+(kln(nkln(n+1))). This formulation of Dvoretzky's theorem for large dimensional sections is a generalization with a new proof of the result due to Milman and Schechtman for centrally symmetric convex bodies. A sharper estimate holds for the n-dimensional simplex.

Bibliography

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Pages:
191-200
Main language of publication
English
Received
1997-04-21
Published
1998
Exact and natural sciences