Emulating Observables from Chiral EFT Potentials

Bayesian nucleon-nucleon (NN) uncertainty quantification (UQ) has proven useful in helping understand to what extent our models work, but the process is known to be computationally expensive when using direct calculation methods. Recently, the development of emulators has accelerated in low-energy nuclear physics due to their accuracy and computational efficiency in predicting bound state and scattering observables for different potentials, making them a promising candidate for UQ. Of the currently available emulators, eigenvector continuation (EC) has demonstrated its ability in making accurate predictions for potentials in both coordinate and momentum space. The emulation process is performed by creating a basis of eigensolutions for several sets of known parameters to accurately interpolate and extrapolate solutions for the same Hamiltonian with different parameters. In addition, a two-body scattering emulator that employs a basis of scattering matrices has recently emerged as a strong alternative to EC. Here we compare the predictive capabilities of both emulators for a variety of observables and chiral effective field theory potentials.