The New Era of Gravitational-Wave Physics and Astrophysics

Coordinators: Duncan Brown, Daniel Holz, Brian Metzger, and Alberto Sesana

Scientific Advisors: Alessandra Buonanno, Selma E. de Mink, Frans Pretorius, and Eliot Quataert

The detection of binary black hole mergers by the Laser Interferometer Gravitational-wave Observatory (LIGO) has initiated the era of gravitational-wave astronomy. These events are driving a revolution in our understanding of the warped side of the universe and in the life and death of massive stars. The sensitivity of the Advanced LIGO detectors continue to improve and the Virgo detector will soon be making joint observations with LIGO. Beyond the ground-based network of detectors, Pulsar Timing Arrays (PTAs) are searching for very low-frequency waves from massive black holes, and the recent success of the LISA pathfinder mission shows great promise for the development of LISA and the opening of the milihertz frequency window.

The gravitational-wave sources detected by LIGO are of fundamental interest to both physicists and astronomers. Observed coalescence rates, masses, spins, and distances allow us to explore the processes driving stellar evolution. Gravitational waves from binary black holes will allow us to test general relativity in the strong-field regime. Binaries containing neutron stars will probe the equation of state of nuclear matter. The direct detection of electromagnetic counterparts (e.g., short gamma-ray bursts or kilonovae) to gravitational-wave sources would provide unprecedented physical and astrophysical insights. All of these goals require collaboration between astrophysicists, gravitational-wave astronomers, and relativists. This program will bring together a broad group of experts to discuss the astrophysics and fundamental physics that can be learned from the observations available at the time of the program.