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THE NON-COMMUTATIVE KHINTCHINE INEQUALITIES FOR $0<p<1$

Published online by Cambridge University Press:  14 October 2015

Gilles Pisier
Affiliation:
Department of Mathematics, Texas A&M University, College Station, TX 77843-3368, USA ([email protected])
Éric Ricard
Affiliation:
Laboratoire de Mathématiques Nicolas Oresme, Université de Caen Normandie, BP 5186, F 14032, Caen, France ([email protected])

Abstract

We give a proof of the Khintchine inequalities in non-commutative $L_{p}$-spaces for all $0<p<1$. These new inequalities are valid for the Rademacher functions or Gaussian random variables, but also for more general sequences, for example, for the analogues of such random variables in free probability. We also prove a factorization for operators from a Hilbert space to a non-commutative $L_{p}$-space, which is new for $0<p<1$. We end by showing that Mazur maps are Hölder on semifinite von Neumann algebras.

Type
Research Article
Copyright
© Cambridge University Press 2015 

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