Speaker
Description
I will present a novel method for extracting observables for two-body scattering systems from a set of generating functions, with full spin dependence. The approach uses the classical limit of the logarithm of the quantum S-matrix as generating functions. The 4-point matrix element of Log(S) gives the radial action, corresponding to conservative effects, whereas the higher-point contributions encode radiative information. The observables, such as momentum impulse, orbital angular momentum, and waveform, are obtained by applying differential operators, which are constructed from Dirac brackets and the generating functions, to the initial value of the observable. We demonstrate its power by calculating new high-precision results, including the impulse and spin kick for a probe in Kerr up to $O(G^6 s^4)$, and the change in angular momentum for generic masses up to $O(G^2 s^11)$. Via analytic continuation, we can also provide information about bound orbits, such as their fundamental frequencies.
