Quantum Monte Carlo study of inhomogeneous neutron matter and neutron stars, S. Gandolfi, Los Alamos National Laboratory,  Los Alamos, New Mexico, USA − Recent advances in experiments of the symmetry energy of nuclear matter and in neutron star observations, yield important new insights on the equation of state of neutron matter at nuclear densities.  In this regime the EOS of neutron matter plays a critical role in determining the mass-radius relationship for neutron stars.  We show how microscopic calculations of neutron matter make clear predictions for the relation between the isospin-asymmetry energy of nuclear matter and its density dependence, and the maximum mass and radius for a neutron star.  On the other side, the properties of inhomogeneous neutron matter at low to moderate densities are very important to describe the neutron star crust, and we show how microscopic calculations of confined neutrons can put severe constraints on density functionals used to describe heavy nuclei and the crust.