Model reduction methods for nuclear emulators

TL;DR

This paper reviews model order reduction techniques for creating fast, accurate emulators of complex nuclear systems, highlighting eigenvector continuation and projection methods to improve computational efficiency.

Contribution

It provides a comprehensive overview of MOR methods applied to nuclear emulators, connecting them with broader mathematical frameworks and potential cross-disciplinary applications.

Findings

Eigenvector continuation as a special MOR case

Introduction to Ritz and Galerkin projection methods

Potential for broader applications in nuclear physics

Abstract

The field of model order reduction (MOR) is growing in importance due to its ability to extract the key insights from complex simulations while discarding computationally burdensome and superfluous information. We provide an overview of MOR methods for the creation of fast & accurate emulators of memory- and compute-intensive nuclear systems. As an example, we describe how "eigenvector continuation" is a special case of a much more general and well-studied MOR formalism for parameterized systems. We continue with an introduction to the Ritz and Galerkin projection methods that underpin many such emulators, while pointing to the relevant MOR theory and its successful applications along the way. We believe that this will open the door to broader applications in nuclear physics and facilitate communication with practitioners in other fields.