We explain new ideas that come from modern scattering theory of
elementary particles that 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, generalized unitarity, improved
integration methods and double-copy relations between gauge and
gravity theories. After introducing these concepts, we explain how
these ideas can be transfered to the gravitational wave problem and
how they are being used to push forward the state of the art in the
post-Minkowskian framework for the binary black hole inspiral problem.
As examples, we present new results at the 3rd and 4th post-Minkowskian
orders.