Radiation Reaction and Gravitational Waves at Fourth Post-Minkowskian Order

TL;DR

This paper calculates the total impulse, radiated momentum, and energy flux for non-spinning binary systems in general relativity at the fourth Post-Minkowskian order, advancing gravitational wave modeling.

Contribution

It introduces a comprehensive fourth-order Post-Minkowskian calculation including radiation-reaction effects using advanced effective field theory and multi-loop techniques.

Findings

Total radiated spacetime momentum derived.

Energy flux for generic orbits computed.

Results agree with previous partial calculations.

Abstract

We obtain the total impulse in the scattering of non-spinning binaries in general relativity at fourth Post-Minkowskian order, i.e. ${\cal O}(G^4)$, including linear, nonlinear, and hereditary radiation-reaction effects. We derive the total radiated spacetime momentum as well as the associated energy flux. The latter can be used to compute gravitational-wave observables for generic (un)bound orbits. We employ the ("in-in") Schwinger-Keldysh worldline effective field theory framework in combination with modern "multi-loop" integration techniques from collider physics. The complete results are in agreement with various partial calculations in the Post-Newtonian/Minkowskian expansion.