Joint Theory Seminar: Gustav Jakobsen (Humboldt University)

Title:Spinning Black Hole Scattering at 5PM Order

Abstract: I will present recent work on the dynamics of spinning black holes in the post-Minkowskian (PM) approximation. Here, one works in a weak-field expansion and black holes or other compact objects are described in an effective field theory framework as point-like particles with finite-size and spin effects present as effective Wilson couplings. In this setting, I will focus on high precision computations of observables of the scattering of spinning (Kerr) black holes. Interestingly, this expansion can be arranged in a loop expansion in close analogy to high-precision computations in particle physics. I will present state-of-the-art results at the 5PM order corresponding to 4-loop Feynman integrals which require advanced loop integration techniques imported from quantum field theory (QFT). More generally, several methods of QFT may advantageously be imported to the (classical) two-body problem as done, for example, in the worldline QFT formalism which I will present and which greatly streamlines classical perturbative computations. A main application of these results is in gravitational wave physics which, however, requires a resummation of the perturbative results where I will discuss recent work on spinning, post-Minkowskian effective-one-body resummations and comparisons with numerical relativity.

Student session: 13:10