Relativistic Gravitation and Astrophysics

Washington University, Saint Louis MO

Investigators

Abstract

The likely detection of gravitational waves from astrophysical sources will open a new window for astronomy and provide new tests of Einstein's theory of general relativity. Interpreting the observations and advancing this new field will require accurate theoretical gravitational waveforms calculated from the theory. This project will endeavor to provide the needed waveforms, by solving Einstein's equations systematically in an approximation known as the post-Newtonian method. Development of a novel diagnostic tool, based on higher-order post-Newtonian methods, to elucidate the physical content of numerical simulations of black-hole and neutron-star binary inspiral will be continued. Ways to use gravitational-wave data to test alternative theories of gravity will also be studied. This includes testing the scalar-tensor alternative theories and theories in which the graviton has a mass, by observing gravitational waves from inspiralling compact binaries. Such tests could provide verification of Einstein's theory in entirely new regimes. Education and training of graduate and undergraduate students and of a post-doctoral researcher will be integrated into the research program. The PI will continue to give public lectures on topics related to this research, bringing understanding of the validity and implications of Einstein's ideas to the broader community. He will prepare an update of his comprehensive review article on experimental gravitation for the web-based journal Living Reviews in Relativity, update his popular book ``Was Einstein Right?'' and enhance his current website with web pages providing information on testing fundamental physics with gravitational waves. The work on equations of motion and gravitational wave forms will impact the field of astronomy, as gravitation-wave observations, which rely upon these calculations, become a reality. The research on post-Newtonian diagnostics will foster closer ties between the post-Newtonian experts and numerical relativity experts, leading to more realistic simulations of the important final phase of binary inspiral.