Radiated momentum and radiation-reaction in gravitational two-body scattering including time-asymmetric effects

TL;DR

This paper calculates the gravitational radiation and momentum transfer in two-body scattering at high post-Newtonian accuracy, emphasizing the importance of time-asymmetric effects for consistent theoretical modeling.

Contribution

It introduces the first comprehensive inclusion of time-asymmetric effects in high-order post-Newtonian calculations of gravitational scattering.

Findings

Time-asymmetric effects are crucial for mass-polynomiality in the post-Minkowskian expansion.

Imposing mass-polynomiality constrains radiative contributions at 4PM and 5PM orders.

The work enhances the theoretical understanding of gravitational wave emission in scattering events.

Abstract

We compute to high post-Newtonian accuracy the 4-momentum (linear momentum, and energy), radiated as gravitational waves in a two-body system undergoing gravitational scattering. We include, for the first time, all the relevant {\it time-asymmetric} effects that arise when consistently going three post Newtonian orders beyond the leading post Newtonian order. We find that the inclusion of time-asymmetric radiative effects (both in tails and in the radiation-reacted hyperbolic motion) is crucial to ensure the mass-polynomiality of the post-Minkowskian expansion ($G$ expansion) of the radiated 4-momentum. Imposing the mass-polynomiality of the corresponding individual impulses determines the conservativelike radiative contributions at the fourth post-Minkowskian order, and strongly constrains them at the fifth post-Minkowskian order.