Sharp commutator estimates of all order for Coulomb and Riesz modulated energies

TL;DR

This paper establishes sharp, high-order functional inequalities controlling derivatives of Coulomb and Riesz modulated energies, with applications to mean-field limits and statistical mechanics.

Contribution

It extends and sharpens inequalities for modulated energies, introduces a novel commutator-based approach, and develops local regularity theory for these commutators.

Findings

Proves sharp inequalities controlling derivatives of modulated energies.

Identifies commutators as solutions to degenerate elliptic equations.

Achieves optimal convergence rates in mean-field limits.

Abstract

We prove functional inequalities in any dimension controlling the iterated derivatives along a transport of the Coulomb or super-Coulomb Riesz modulated energy in terms of the modulated energy itself. This modulated energy was introduced by the second author and collaborators in the study of mean-field limits and statistical mechanics of Coulomb/Riesz gases, where control of such derivatives by the energy itself is an essential ingredient. In this paper, we extend and improve such functional inequalities, proving estimates which are now sharp in their additive error term, in their density dependence, valid at arbitrary order of differentiation, and localizable to the support of the transport. Our method relies on the observation that these iterated derivatives are the quadratic form of a commutator. Taking advantage of the Riesz nature of the interaction, we identify these commutators as solutions to a degenerate elliptic equation with a right-hand side exhibiting a recursive structure in terms of lower-order commutators and develop a local regularity theory for the commutators, which may be of independent interest. These estimates have applications to obtaining sharp rates of convergence for mean-field limits, quasi-neutral limits, and in proving central limit theorems for the fluctuations of Coulomb/Riesz gases. In particular, we show here the expected $N^{\frac{\mathsf{s}}{\mathsf{d}}-1}$-rate in the modulated energy distance for the mean-field convergence of first-order Hamiltonian and gradient flows.