The remarkable detection of gravitational waves by the LIGO/Virgo collaboration has opened a new window into the cosmos. In this seminar we explain how particle theorists can help out with calculations directly relevant for gravitational-wave emission from compact astrophysical objects. The past decade has seen enormous advances in our ability to compute quantum scattering amplitudes making seemingly impossible calculations tractable. These advances include ideas such as the duality between color and kinematics, double-copy relations and generalized unitarity, and improved integration methods. After introducing these concepts, we explain how these ideas are transferred to state-of-the-art calculations for the binary black hole inspiral problem.