We present a new method to compute the energy per particle in nuclear matter at low densities. It relates the energy per particle in nuclear matter at low densities directly to the nucleon-nucleon scattering amplitude in the vacuum.
The results are independent of any regulator and can be used for many purposes, including the calculation of the equation of state of nuclear matter at low densities. In particular, the results for pure neutron matter can be used
to constrain the equation of state of neutron stars at low densities, which is important for the determination of the equation of state of neutron stars from first principles.
