A self-consistent theory for exchange and correlation effects in an electron gas

A self-consistent theory for electron correlations formulated so as to satisfy both the compressibility and spin susceptibility sum rules within the framework of the so-called generalised random phase approximation, is used for studying numerically correlation effects on electron gas properties at metallic densities. The physical implication of the self-consistency requirement in the theory is discussed from the diagrammatic viewpoint of perturbation theory.