“Gravitational Waves and Binary Black Holes”

Thibault Damour (Institut des Hautes Etudes Scientifiques, Bures sur Yvette, France)

The recent discovery of several gravitational wave events by the two Laser Interferometer Gravitational-Wave Observatory (LIGO) interferometers, and by the Virgo interferometer, has brought the first direct evidence for the existence of black holes, and has also been the first  observation of gravitational waves in the wave-zone. The talk will review the theoretical developments on the motion and gravitational radiation of binary black holes that have been crucial in interpreting the LIGO-Virgo events as being emitted by the coalescence of two black holes. In particular, we shall present the Effective One-Body (EOB) formalism which led to the first prediction for the gravitational-wave signal emitted by coalescing black holes. We shall also discuss how the EOB formalism can provide a bridge between quantum gravitational scattering amplitudes and the classical Hamiltonian description of the general relativistic two-body problem.