Scattering of tidally interacting bodies in post-Minkowskian gravity

Understand

The post-Minkowskian approach to gravitationally interacting binary systems ({\it i.e.}, perturbation theory in $G$, without assuming small velocities) is extended to the computation of the dynamical effects induced by the tidal deformations of two extended bodies, such as neutron stars.

• Our derivation applies general properties of perturbed actions to the effective field theory description of tidally interacting bodies.
• We compute several tidal invariants (notably the integrated quadrupolar and octupolar actions) at the first post-Minkowskian order.
• The corresponding contributions to the scattering angle are derived.