Thorne 9417371 Theoretical research will be conducted at the interface between general relativity theory and astrophysics studying the generation of gravitational waves by astrophysical objects. A minor additional effort will study non-gravitational wave aspects of black holes and neutron stars. The gravitational-wave research will be focused on waves detectable by LIGO (the Laser Interferometer Gravitational-Wave Observatory) to identify what wave-generation computations are needed for LIGO. Of special concern will be the waves produced in the last ~10 minutes of the life of a binary system made up from neutron stars or black holes. During these 10 minutes the two bodies spiral inward, producing approximately 10,000 wave cycles that carry detailed information about the bodies' orbit, masses, and spins. During the last few milliseconds the bodies violently coalesce, producing waves that carry information about the equation of state of nuclear matter in the neutron star case and about the nonlinear dynamics of space-time curvature in the black hole case. The resulting waveforms must be computed to high accuracy for use as theoretical templates in analyzing LIGO data. ***