This is an announcement for the paper "Remarks on the KLS conjecture and Hardy-type inequalities" by Alexander V. Kolesnikov and Emanuel Milman.
Abstract: We generalize the classical Hardy and Faber-Krahn inequalities to arbitrary functions on a convex body $\Omega \subset \mathbb{R}^n$, not necessarily vanishing on the boundary $\partial \Omega$. This reduces the study of the Neumann Poincar'e constant on $\Omega$ to that of the cone and Lebesgue measures on $\partial \Omega$; these may be bounded via the curvature of $\partial \Omega$. A second reduction is obtained to the class of harmonic functions on $\Omega$. We also study the relation between the Poincar'e constant of a log-concave measure $\mu$ and its associated K. Ball body $K_\mu$. In particular, we obtain a simple proof of a conjecture of Kannan--Lov'asz--Simonovits for unit-balls of $\ell^n_p$, originally due to Sodin and Lata{\l}a--Wojtaszczyk.
Archive classification: math.SP math.FA
Remarks: 18 pages
Submitted from: emanuel.milman@gmail.com
The paper may be downloaded from the archive by web browser from URL
http://front.math.ucdavis.edu/1405.0617
or