Ground-states for the liquid drop and TFDW models with long-range attraction

TL;DR

This paper proves the existence of ground-states for the liquid drop and TFDW models with long-range attractive potentials, extending previous results to all masses under these conditions.

Contribution

It establishes the existence of ground-states for both models with long-range potentials, using concentration-compactness and compactness results for sets of finite perimeter.

Findings

Ground-states exist for all masses with long-range potentials.

The methods adapt classical concentration-compactness and finite perimeter compactness results.

Results apply to models with potentials decaying slower than Newtonian.

Abstract

We prove that both the liquid drop model in $\mathbb{R}^3$ with an attractive background nucleus and the Thomas-Fermi-Dirac-von Weizs\"{a}cker (TFDW) model attain their ground-states \emph{for all} masses as long as the external potential $V(x)$ in these models is of long range, that is, it decays slower than Newtonian (e.g., $V(x)\gg |x|^{-1}$ for large $|x|$.) For the TFDW model we adapt classical concentration-compactness arguments by Lions, whereas for the liquid drop model with background attraction we utilize a recent compactness result for sets of finite perimeter by Frank and Lieb.