# Gravitational Wave Theory

Einstein's theory of General Relativity predicts that accelerating massive bodies will produce gravitational waves, vibrations in the fabric of spacetime. Gravitational wave interferometers in the United States [Laser Interferomer Gravitational Observatory (LIGO)], India (LIGO-India), Italy (Virgo), Germany (GEO) and Japan (KAGRA) will detect such waves before 2020. Space-borne detectors, such as the Laser Interferometer Space Antenna (LISA) mission, are also being planned by both NASA and the European Space Agency. The detection of gravitational waves requires their precise theoretical modeling to allow for the construction of waveform templates with which to filter the noise data.

The XGI focuses on the analytical modeling of gravitational waves emitted during the inspiral and merger of compact objects, such as black holes and neutron stars. Such modeling requires the solution to the Einstein equations, which we perform analytically via mathematical series techniques. During the inspiral, when the compact objects have small velocities relative to the speed of light, we employ post-Minkowskian and post-Newtonian techniques to solve the Einstein equations. After the merger, as the remnant compact object settles down to its final stationary state, we employ black hole perturbation theory to solve the field equations. These solutions then allow us to predict the gravitational wave observable from which to construct template filters.