I will illustrate the hidden simplicity relating the classical limits of different theories, including $N=8$ supergravity, electrodynamics, and certain scalar theories. Despite this simplicity, extracting observables from the classical limit becomes rapidly computationally expensive at higher orders. This motivates a complementary approach to weak-field gravity, based on the Schwinger–Keldysh path integral, in which the dynamics and waveform are computed for generic relativistic worldlines, bypassing several technical intermediate steps in the computation of gravitational-wave observables.
By Shiraz Minwalla
By Robin Karlsson
By Anatoly Dymarsky
By Hong Liu
By Mariana Grana
By Mukund Rangamani
By Anton Kapustin
By Anna Wolz
By Thibault Damour
By Colin Guillarmou
By Frank Ferrari
By Giovanni Felder
