Relativistic brueckner-hartree-fock theory: An AB initio approach for finite nuclei

Attempts are discussed to derive covariant density functionals ab initio, i.e. from the bare nucleon-nucleon forces. They are based on the Relativistic Brueckner-Hartree-Fock (RBHF) theory which, in most cases, has been applied for nuclear matter. For semi-microscopic functionals, such calculations are used to derive the density dependence of the parameters. In this way, only very few phenomenological parameters are left for the fine tuning. The RBHF calculations in finite nuclear systems are used to obtain additional formation as, for instance, the strength of effective tensor forces, which are difficult to obtain in a phenomenological way from the data.