On a quantitative reversal of Alexandrov's inequality
Abstract
Alexandrov's inequalities imply that for any convex body , the sequence of intrinsic volumes is non-increasing (when suitably normalized). Milman's random version of Dvoretzky's theorem shows that a large initial segment of this sequence is essentially constant, up to a critical parameter called the Dvoretzky number. We show that this near-constant behavior actually extends further, up to a different parameter associated with . This yields a new quantitative reverse inequality that sits between the approximate reverse Urysohn inequality, due to Figiel--Tomczak-Jaegermann and Pisier, and the sharp reverse Urysohn inequality for zonoids, due to Hug--Schneider. In fact, we study concentration properties of the volume radius and mean width of random projections of and show how these lead naturally to such reversals.
Keywords
Cite
@article{arxiv.1702.05762,
title = {On a quantitative reversal of Alexandrov's inequality},
author = {Grigoris Paouris and Peter Pivovarov and Petros Valettas},
journal= {arXiv preprint arXiv:1702.05762},
year = {2017}
}
Comments
Corrected the probability estimate in the lower small deviation inequality (1.12) in Theorem 1.2