Effective Field Theory for Neutron Stars with Genuine Many-body Forces

Abstract: The aim of our contribution is to shed some light on open questions facing the high density nuclear many-body problem. We focus our attention on the conceptual issue of naturalness and its role for the baryon-meson coupling for nuclear matter at high densities. As a guideline for the strengths of the various couplings the concept of naturalness has been adopted. In order to encourage possible new directions of research, we discuss relevant aspects of a relativistic effective theory for nuclear matter with natural parametric couplings and genuine many-body forces. Among other topics, we discuss in this work the connection of this theory with other known effective Quantum Hadrodynamics (QHD) models found in literature and how we can potentially use our approach to describe new physics for neutron stars. We also show some preliminary results for the equation of state, population profiles and mass-radius relation for neutron stars assuming local charge neutrality and beta equilibrium.