Convergence rates for energies of interacting particles whose distribution spreads out as their number increases

TL;DR

This paper analyzes the convergence rates of particle system energies to continuum energies in scenarios where particles spread out due to weakening confining potentials, with implications for approximation theory and plasticity.

Contribution

It provides new bounds on energy differences and potential discrepancies for particle systems with weak confining potentials, extending existing theoretical frameworks.

Findings

Bounds on energy differences between particle and continuum systems

Demonstration of bounds' usefulness in approximation theory and plasticity

Introduction of a new upper bound on the continuum energy minimizer

Abstract

We consider a class of particle systems which appear in various applications such as approximation theory, plasticity, potential theory and space-filling designs. The positions of the particles on the real line are described as a global minimum of an interaction energy, which consists of a nonlocal, repulsive interaction part and a confining part. Motivated by the applications, we cover non-standard scenarios in which the confining potential weakens as the number of particles increases. This results in a large area over which the particles spread out. Our aim is to approximate the particle interaction energy by a corresponding continuum interacting energy. Our main results are bounds on the corresponding energy difference and on the difference between the related potential values. We demonstrate that these bounds are useful to problems in approximation theory and plasticity. The proof of these bounds relies on convexity assumptions on the interaction and confining potentials. It combines recent advances in the literature with a new upper bound on the minimizer of the continuum interaction energy.