Bayesian approach for many-body uncertainties in nuclear structure: Many-body perturbation theory for finite nuclei

TL;DR

This paper introduces a Bayesian framework to quantify many-body uncertainties in nuclear structure calculations, improving the systematic assessment of theoretical errors in ab initio nuclear models.

Contribution

It develops a Bayesian approach to evaluate many-body truncation uncertainties in perturbation theory for finite nuclei, advancing uncertainty quantification in nuclear physics.

Findings

Applied to a wide range of nuclei across the nuclear chart.

Used chiral effective field theory interactions for calculations.

Provides a systematic method for uncertainty estimation.

Abstract

A comprehensive assessment of theoretical uncertainties defines an important frontier in nuclear structure research. Ideally, theory predictions include uncertainty estimates that take into account truncation effects from both the interactions and the many-body expansion. While the uncertainties from the expansion of the interactions within effective field theories have been studied systematically using Bayesian methods, many-body truncations are usually addressed by expert assessment. In this work we use a Bayesian framework to study many-body uncertainties within many-body perturbation theory applied to finite nuclei. Our framework is applied to a broad range of nuclei across the nuclear chart calculated from two- and three-nucleon interactions based on chiral effective field theory. These developments represent a step towards a more complete and systematic quantification of uncertainties in \emph{ab initio} calculations of nuclei.