by HF, as far as nuclear binding energies are concerned [@RPP2006].

In a recent publication [@PPH2006] we employed the UCOM Hamiltonian in standard, self-consistent RPA calculations to study nuclear giant resonances. The ground state was described by the uncorrelated HF state, as usual. The main focus was on the isoscalar (IS) giant monopole resonance (GMR), the isovector (IV) giant dipole resonance (GDR), and the IS giant quadrupole resonance (GQR). Highly collective states were indeed obtained for various closed-shell nuclei ranging from [$^{16}$[O]{}]{} to [$^{208}$[Pb]{}]{}. We achieved a reasonable agreement with the experimental centroid energies of the IS GMR. By contrast, the energies of the IV GDR and the IS GQR were overestimated by several MeV.

Obviously, the $V_{\text{UCOM}}$ is not a traditional effective interaction. Partly because no long-range correlations are (effectively) included in the UCOM, the corresponding nucleon effective mass in nuclear matter obtained in a HF calculation is very low (less than half the bare nucleon mass). This is confirmed by the HF results in finite nuclei: the single-particle level density was found too low. It is also manifested by the above-mentioned RPA results on the GQR and GDR centroids. From the preceding discussion it follows that, besides the 