Giant Dipole Resonance in light and heavy nuclei beyond selfconsistent mean field theory

While bulk properties of stable nuclei are successfully reproduced by mean-field theories employing effective interactions, the dependence of the centroid energy of the electric giant dipole resonance on the nucleon number A is not. This problem is cured by considering many-particle correlations beyond mean-field theory, which we do within a selfconsistent generalization of the {\em Quasiparticle Time Blocking Approximation} [1,2]. The electric giant dipole resonances in $^{16}$O, $^{40}$Ca, and $^{208}$Pb are calculated using two new Skyrme interactions. Perspectives for an extension to effective field theories[3] are discussed.\\[4pt] [1] V. Tselyaev et al., Phys.Rev.C{\bf 75}, 014315(2007).\\[0pt] [2] N. Lyutorovich et al., submitted to Phys.Rev.Lett.\\[0pt] [3] S. Krewald et al., Prog.Part.Nucl.Phys.{\bf 67}, 322(2012).