Title: From chiral effective field theory to perturbative QCD: A Bayesian model mixing approach to neutron star matter

Abstract: Constraining the equation of state (EOS) of strongly interacting, dense matter is the focus of significant experimental, observational, and theoretical effort. While chiral effective field theory (EFT) can describe the EOS between the typical densities of nuclei and those in the outer cores of neutron stars, perturbative QCD (pQCD) can be applied to properties of deconfined quark matter, both with quantified theoretical uncertainties.

However, describing the full range of densities in between with a single EOS that has well-quantified uncertainties is a challenging problem. Bayesian model mixing (BMM) can help bridge the gap between the two theories.

In this talk, I will present a BMM framework that can combine EOS constraints from different density regions in a principled way to construct a globally predictive, composite EOS model based on Gaussian processes (GPs). I will discuss applications of this BMM framework to the EOS and structure of neutron stars, as well as the statistical uncertainty quantification of the underlying microscopic EOS calculations.