Speaker
Description
In this talk, we develop a black-hole response formulation of worldline quantum field theory (WQFT) tailored to the gravitational self-force (SF) expansion. By integrating out the primary black hole’s worldline and graviton fluctuations, we obtain an effective action built from black-hole response functions. In this, the one-point response function encodes the exact background metric, the two-point response function describes the scattering of a gravitational wave off the black hole, and higher-point functions provide effective vertices for a systematic gravitational SF expansion.
As a first application, we consider a massless primary source, corresponding to the Aichelburg-Sexl shockwave or an ultra-boosted black hole. We show that the one-point response resums to the exact shockwave metric. Next, we discuss the computation of the exact in G two-point response by resumming the full post-Minkowskian series. We conclude with an outlook on how to obtain the 1SF impulse and waveform in the high-energy regime with this framework.