9513717 Yan This proposal is to investigate the fundamental constituents of matter and the forces between them on two fronts. One aim is to test and to extend the current understanding of the "Standard Model" of subatomic phenomena in terms of quarks, leptons, gluons, weak bosons, and their interactions. This research will also highlight the interplay between particle physics and astrophysics, as well as mainstream topics in astrophysics such as the mechanism for supernova explosions and the solar-neutrino problem. The second major theme is the search for a unified theory of all interactions, and closely related problems in such diverse fields as mathematical physics, statistical mechanis and condensed matter physics. ***
