9421309 Baym This project aims to develop the fundamental theory of nuclear and other many-particle systems including astrophysical and condensed matter applications. It includes basic studies of the quark-gluon plasma, hadron structure, nuclear forces, the structure of nuclei, nuclear and hadronic matter. A wide range of electron-nucleus and hadron-nucleus and hadron-nucleus scattering experiments and heavy-ion collisions are analyzed in conjunction with these basic studies. The emphasis in astrophysics is on understanding neutron star structure and evolution, low- energy nuclear reactions, and the effect of phase transitions in the early universe. Fundamental problems in the theory of quantum liquids, quantum liquid drops, superconductivity and superfludity are also studied. ***