Description
I will introduce the Eikonal approximation in gravity from the partial waves expansion, which allows us to extract quantities such as the time delay or the deflection angle from scattering amplitudes.
Positivity of the time delay defines a notion of causality in gravity usually referred to as "asymptotic causality". I will discuss how asymptotic causality is satisfied at loop level, by presenting the case of the "photon self-stress" (2108.05896), where quantum corrections to the time delay of a photon are obtained considering 1-loop contributions to its coupling to gravity. I will also comment on another notion of causality, called "bulk causality".
Author
Giulia Isabella
(IJCLab)
