Relativistic nuclear field theory and its applications: from fundamental interactions to nuclear data

I will present relativistic nuclear field theory (RNFT) as an approach to the nuclear many-body problem, which is based on a QHD meson-nucleon Lagrangian and applies quantum field theory to finite nuclei. This approach connects consistently the high-energy scale of heavy mesons, the medium-energy range of pions, and the low-energy domain of emergent collective vibrations (phonons). Mesons and phonons build up the effective interaction in various channels, in particular, the phonon-exchange part takes care of the retardation effects, which are responsible for the fragmentation of single-particle states, spreading of collective giant resonances and soft modes, formation of the low-energy spectra and various reaction rates with significant consequences for astrophysics and fundamental aspects of weak processes in nuclei. RNFT gives a rigorous formulation for one-nucleon and few-nucleon propagators in the strongly correlated medium and, thereby, allows calculations of all nuclear structure observables taking into account high-order nucleonic correlations in a non-perturbative manner. The latter stipulates a higher precision, while a parameter-free character and Lorentz covariance increase the predictive power of RNFT considerably as compared to the traditional nuclear structure models. Results for excitation spectra in various channels in medium-mass and heavy nuclei within and outside the valley of stability will be presented in comparison to data and discussed in light of their applications to nuclear data, such as contributions to RIPL, NuDat and photonuclear data libraries. Current developments on the pion degree of freedom and perspectives toward a fully ab initio approach as well as a larger range of applications will be outlined.