Connecting many-body methods for a precise and predictive description of atomic nuclei

Abstract:  Nuclei are unique quantum many-body systems which can exhibit a very rich variety of behaviors. While historically the many-body methods have been developed in order to tackle specific mass regions or physical phenomena, one of the goals of modern nuclear theory is to connect and unify these methods in order to ultimately reach a universal, precise and predictive description of nuclei. In my talk I will discuss two approaches that follow this direction: 1) The self-consistent multiparticle-multihole configuration mixing method, at the crossroads between shell models and mean-field methods, considers the nuclear wave function as a superposition of Slater determinants built on an optimized single-particle basis that is solution of a generalized mean-field equation. I will present first applications of this approach to ground and excited properties of light and sd-shell nuclei; and will discuss future plans in the context of FRIB physics. 2) The relativistic nuclear field theory starts from a relativistic mean-field approximation and builds inter-nucleon correlations that emerge from the coupling between single nucleons and collective vibrations of the nucleus. I will show recent applications of this approach to charge-exchange modes and weak-interaction processes in mid-mass and heavy nuclei that will be investigated by FRIB.