Neutron matter and light nuclei from Quantum Monte Carlo calculations with local chiral interactions
Abstract: The neutron-matter equation of state connects several physical systems over a wide density range. Among these are neutron-rich nuclei, which are relevant for the description of the r-process, and neutron stars, which contain the densest form of matter we know to exist in the cosmos. An accurate description of the neutron-matter equation of state requires precise many-body methods in combination with a systematic theory for nuclear forces. Continuum Quantum Monte Carlo (QMC) methods are among the most precise many-body methods available to study strongly interacting systems at finite densities. They project out the ground-state wave function of the system by propagating a trial wave function in imaginary time but require local interactions as input. Chiral effective field theory (EFT) is a systematic theory for nuclear forces that allows to develop consistent two- and three-nucleon interactions and enables calculations with controlled theoretical uncertainties. Chiral EFT makes use of a momentum-space expansion of nuclear forces based on the symmetries of Quantum Chromo- dynamics, but contains several sources of nonlocality. In this talk I will explain how to combine chiral EFT interactions and QMC calculations and present recent QMC results for the neutron-matter equation of state and light nuclei with local chiral NN and 3N interactions. I will finally address open problems with local chiral interactions.