Gravitational waves and fundamental (astro)physics

Gravitational waves, as predicted by Einstein one hundred years ago, have been detected by the advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) in September last year. This finding marks the beginning of gravitational-wave astronomy. From now on, we are able to probe our universe using both long-range forces in nature. 

In the foreseeable future, the gravitational wave astronomy will be exponentially growing, with more detectors targeting gravitational waves at different frequencies and more events detected every week. This will provide us great opportunities but also impose challenges as well. In the first part of my talk, I will discuss the physics of gravitational wave detectors, emphasizing its basic principles and dominant noise sources, as well as ongoing efforts to improve detector sensitivity to fulfill the growing need. In the second half of my talk, I will discuss the astrophysics of gravitational-wave sources - especially compact sources such as black holes and neutron stars. I shall explain the spacetime dynamics, gravitational-wave emission during compact binary mergers and possible electromagnetic radiation from these compact objects. In the next few years with new gravitational-wave observations and possible electromagnetic counterpart measurements, we may dramatically improve our understandings on the astrophysics of these sources.