Theoretical Studies in Gravitation and Astrophysics

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

This reseach spans several problems involving general relativity, the generation of gravitational radiation, relativistic hydrodynamics, magnetohydrodynamics, and stellar dynamics. A common thread uniting the different theoretical topics is the crucial role of gravitation, especially relativistic gravitation. Compact objects (e.g., black holes and neutron stars) provide the principal forum, and the dynamics of matter in a strong gravitational field is a major theme. Some of the topics under investigation include the inspiral and coalescence of binary neutron stars and black holes, the generation of gravitational waves from binaries and other promising astrophysical sources of gravitational radiation, gravitational collapse, the stability of rotating neutron stars and supermassive stars and the final fate of unstable stars, and the formation of supermassive black holes now observed in the cores of galaxies and quasars. Most of these topics represent long-standing, fundamental problems in theoretical physics requiring large-scale computation for solution. Hence the approach involves large-scale computations on parallel machines, as well as analytical modeling. Many of the numerical calculations employ the state-of-the-art computational resources of the UIUC's National Center for Supercomputing Applications (NCSA). They comprise both initial value and evolution computations and treat vacuum spacetimes containing black holes as well as spacetimes containing realistic matter sources. The research bridges the fields of general relativity and astrophysics. The results have important implications for astronomical observations, including those planned for gravitational wave interferometers, such as LIGO and LISA. An appreciable portion of the effort is devoted to the education, training and support of postdoctoral students and a Research Experiences for Undergraduates (REU) team at UIUC in computational astrophysics and relativity. These students collaborate with the PI on the majority of research. The training that each of the PI's students receives in large-scale computations and scientific visualization, as well as in several different areas of theoretical physics and astrophysics, prepares them to pursue professional careers in a broad range of scientific and technical fields. The computer algorithms and numerical codes that are being developed are useful to other groups working in computational physics and astrophysics. The research and outreach activities of the PI and his group help promote the use of computers and visualization tools at all levels of education, as well as the public awareness of some the latest and most exciting developments in gravitation physics and astrophysics.