Self-consistent Green's functions in nuclear matter

A completely self-consistent solution of the nuclear matter problem is studied using Green's functions. Special emphasis is placed on the dynamics of the single-particle properties since they should reflect the non-mean-field features established by electron scattering experiments. The effective interaction between the particles in the medium is obtained from a generalization of Brueckner ladder diagrams that is symmetric with respect to particles and holes and employs full off-shell propagation of the particles. The inclusion of the latter represents a substantial increase in computational effort compared to previous determinations of the effective interaction. However, the feasibility of the calculations is demonstrated for both zero and finite temperatures. This propagation of dressed particles leads to the dramatic disappearance of previously obtained pairing instabilities above normal nuclear matter density (kF = 1.36 fm-1). Self-consistent self-energies, spectral functions, and momentum distributions are presented for two densities corresponding to (kF = 1.36 fm-1) and (kF = 1.45 fm -1). Subtle differences for these quantities are established in comparison to calculations starting from mean-field propagation. These differences lead to a dramatic change in the saturation properties obtained for nuclear matter employing only two-body interactions.