English

A criterion for Talagrand's quadratic transportation cost inequality

Probability 2007-05-23 v3 Functional Analysis

Abstract

We show that the quadratic transportation cost inequality T2T_2 is equivalent to both a Poincar\'e inequality and a strong form of the Gaussian concentration property. The main ingredient in the proof is a new family of inequalities, called modified quadratic transportation cost inequalities in the spirit of the modified logarithmic-Sobolev inequalities by Bobkov and Ledoux \cite{BL97}, that are shown to hold as soon as a Poincar\'e inequality is satisfied.

Keywords

Cite

@article{arxiv.math/0312081,
  title  = {A criterion for Talagrand's quadratic transportation cost inequality},
  author = {Patrick Cattiaux and Arnaud Guillin},
  journal= {arXiv preprint arXiv:math/0312081},
  year   = {2007}
}