Neutron Stars, Effective Field Theory, and the Nuclear Many-Body Problem

by Dr Corbinian Wellenhofer (TU Darmstadt, Institut für Kernphysik, Theoriezentrum )

Monday 11 Jun 2018, 14:15 → 16:45 Europe/Berlin

3344 (TUM - Physics Department - Garching)

The thermodynamic properties of strongly-interacting nuclear matter are essential for nuclear astrophysics,
in particular for the investigation of neutron stars. In particular, the advent of gravitational-wave astronomy
provides renewed motivation for nuclear many-body calculations with systematic uncertainty quantifications.

In this talk, after a short discussion of neutron stars, we review basic concepts and recent developments in the
effective field theory (EFT) approach to the nuclear many-body problem. We start by examining the use of
pionless EFT for the study of fermions at very low energies, and present results up to fourth order in
perturbation theory for the ground-state energy of the dilute Fermi gas. The derivation of nuclear potentials in
chiral EFT is then examined, and we discuss the application of these potentials in advanced perturbative
nuclear many-body calculations.
Finally, it is shown that in this approach the free energy is a nonanalytic smooth function of the isospin asymmetry at low temperatures."