Exact restoration of Galilei invariance in density functional calculations with quantum Monte Carlo

TL;DR

This paper introduces a quantum Monte Carlo method that exactly restores Galilei invariance in nuclear density functional calculations, addressing a common symmetry violation in mean-field approaches.

Contribution

The authors develop a variational quantum Monte Carlo approach that preserves Galilei invariance in density functional calculations, a novel technique for nuclear physics.

Findings

Successfully applied to $^4$He, $^{16}$O, and $^{40}$Ca ground states

Demonstrates the impact of symmetry restoration on nuclear properties

Generalizes the linear optimization method for density-dependent Hamiltonians

Abstract

Galilean invariance is usually violated in self-consistent mean-field calculations that employ effective density-dependent nuclear forces. We present a novel approach, based on variational quantum Monte Carlo techniques, suitable to preserve this symmetry and assess the effect of its violation, seldom attempted in the past. To this aim, we generalize the linear optimization method to encompass the density-dependence of effective Hamiltonians, and study $^4$He, $^{16}$O, and $^{40}$Ca ground-state properties employing the Gogny interaction.