Eigenvector Continuation as an Efficient and Accurate Emulator for Uncertainty Quantification

TL;DR

Eigenvector continuation (EC) is introduced as a fast and precise emulator for nuclear many-body calculations, enabling effective uncertainty quantification in multi-nucleon systems from first principles.

Contribution

The paper presents EC as a novel method for emulating nuclear observables, significantly reducing computational costs and improving accuracy over existing techniques like Gaussian processes.

Findings

EC accurately reproduces ground-state energies and radii in 4He.

EC outperforms Gaussian processes in efficiency and accuracy.

Demonstrates potential for uncertainty quantification in complex nuclear systems.

Abstract

First principles calculations of atomic nuclei based on microscopic nuclear forces derived from chiral effective field theory (EFT) have blossomed in the past years. A key element of such ab initio studies is the understanding and quantification of systematic and statistical errors arising from the omission of higher-order terms in the chiral expansion as well as the model calibration. While there has been significant progress in analyzing theoretical uncertainties for nucleon-nucleon scattering observables, the generalization to multi-nucleon systems has not been feasible yet due to the high computational cost of evaluating observables for a large set of low-energy couplings. In this Letter we show that a new method called eigenvector continuation (EC) can be used for constructing an efficient and accurate emulator for nuclear many-body observables, thereby enabling uncertainty quantification in multi-nucleon systems. We demonstrate the power of EC emulation with a proof-of-principle calculation that lays out all correlations between bulk ground-state observables in the few-nucleon sector. On the basis of ab initio calculations for the ground-state energy and radius in 4He, we demonstrate that EC is more accurate and efficient compared to established methods like Gaussian processes.