CHARGED-BOSON FLUID IN 2 AND 3 DIMENSIONS

We examine various properties of the two- and three-dimensional plasma of charged bosons over an extensive range of densities, especially in the previously less studied low-density regime using a microscopic, v ariational approach. We calculate the ground-state structure and energ etics and compare both our analytical and numerical results with earli er theoretical work. Throughout the entire density regime investigated , good agreement with the results of several Monte Carlo calculations is obtained. Triplet correlations are found to be important for the co nsistency of the equation of state at high densities. To study excitat ions we then allow for time-dependent interparticle correlations. Spec ial attention is paid to the question of a microscopic justification f or the ''local-field factor,'' and the consistency demands imposed by sum rules on microscopic excitation theories. Results for the static d ielectric function epsilon(k,0) and the dynamic structure function S(k ,omega) are presented in three and two dimensions.