PreprintCC BY 4.0arXiv
Optimal MM* bounds for convex bodies
Abstract
Let K⊂Rn be a convex body in isotropic position. We prove the optimal mean-width estimate M*(K)≤ C√(nlog n). The main new ingredient is a geometric inequality relating the Gaussian mean of the support function to its mean under the uniform measure on K, obtained through a heat-flow argument. Combined with the Gaussian-log-concave comparison of Eldan and Lehec and the newly available dimension-free bound on the third-moment parameter κn, this yields the result. The boundedness of κn also makes the mean-norm estimate of Bizeul and Klartag sharp. Combining both estimates yields M(K)M*(K)≤ Clog n, extending Pisier's MM* estimate to non-symmetric convex bodies and to the isotropic position.
Related
- Optimal stability of Pál's isominwidth inequality for ball convex bodies in planes of constant curvature
- Optimal mean width and metric entropy estimates for convex bodies
- Pfaffian Positivity for Convex Kernels and Optimal Matching Bounds
- Near-Optimal Quantum Lower Bounds for Convex Optimization via Fourier Rank
- The Petty Conjecture for Convex Bodies of Revolution
BibTeX
@misc{bizeul2026optimal,
title = {{Optimal MM* bounds for convex bodies}},
author = {Pierre Bizeul},
howpublished = {arXiv},
year = {2026},
month = sep,
doi = {10.48550/arxiv.2607.29458},
eprint = {2607.29458},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2607.29458},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Optimal MM* bounds for convex bodies
AU - Pierre Bizeul
PY - 2026
DA - 2026/09/16
PB - arXiv
DO - 10.48550/arxiv.2607.29458
UR - https://arxiv.org/abs/2607.29458
AB - Let K⊂R^n be a convex body in isotropic position. We prove the optimal mean-width estimate M^*(K)≤ C√(nlog n). The main new ingredient is a geometric inequality relating the Gaussian mean of the support function to its mean under the uniform measure on K, obtained through a heat-flow argument. Combined with the Gaussian-log-concave comparison of Eldan and Lehec and the newly available dimension-free bound on the third-moment parameter κ_n, this yields the result. The boundedness of κ_n also makes the mean-norm estimate of Bizeul and Klartag sharp. Combining both estimates yields M(K)M^*(K)≤ Clog n, extending Pisier's MM^* estimate to non-symmetric convex bodies and to the isotropic position.
ER -