Quantum Gravity Seminar: Benjamin Knorr

Speaker: Benjamin Knorr (Heidelberg U.)

Spacetime coordinates: Wed @ 13:30, Auditorium A

Zoom Link: https://ucph-ku.zoom.us/j/9295289933?omn=67282578176

Title: Asymptotically safe scattering amplitudes and the infrared jungle

Abstract: In this talk I discuss quantum-gravitational scattering amplitudes. First, I will introduce a general framework that is able to describe non-perturbative scattering amplitudes in gravitational QFTs. I will then consider a simple model in which such an amplitude can be computed analytically, based on an asymptotically safe fixed point. I will present the analytical structure of the amplitude, and a potential realisation of the no-global-symmetries conjecture thought to be incompatible with Asymptotic Safety. A key feature of the amplitude is the appearance of gravitational logarithms, which are large in purely massless theories, but can be tamed in massive theories as long as there is a scale separation of the mass and the Planck scale.