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arXiv · 2212.13216

Emulating \emph{ab initio} computations of infinite nucleonic matter

W. G. Jiang·C. Forssén·T. Djärv·G. Hagen
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Abstract

We construct efficient emulators for the \emph{ab initio} computation of the infinite nuclear matter equation of state. These emulators are based on the subspace-projected coupled-cluster method for which we here develop a new algorithm called small-batch voting to eliminate spurious states that might appear when emulating quantum many-body methods based on a non-Hermitian Hamiltonian. The efficiency and accuracy of these emulators facilitate a rigorous statistical analysis within which we explore nuclear matter predictions for $> 10^6$ different parametrizations of a chiral interaction model with explicit $\Delta$-isobars at next-to-next-to leading order. Constrained by nucleon-nucleon scattering phase shifts and bound-state observables of light nuclei up to \nuc{4}{He}, we use history matching to identify non-implausible domains for the low-energy coupling constants of the chiral interaction. Within these domains we perform a Bayesian analysis using sampling/importance resampling with different likelihood calibrations and study correlations between interaction parameters, calibration observables in light nuclei, and nuclear matter saturation properties.

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W. G. Jiang, C. Forssén, T. Djärv, G. Hagen. 2022-12-26. Emulating \emph{ab initio} computations of infinite nucleonic matter. https://doi.org/10.1103/physrevc.109.064314

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