Classical gravitational scattering in the ultra High Energy limit

by Emanuele Rosi

Wednesday Jan 21, 2026, 2:30 PM → 3:30 PM Europe/Rome

Aula Salvini (Laboratori Nazionali di Frascati)

The detection of gravitational waves (GW) after several decades from their formulation opened a new window to observe the universe.

The new generation of GW detectors is expected to span a large parameter space, requiring theoretical physicist to develop different approaches to face the two body problem in General Relativity, each of them based on some perturbative expansion, e.g. Post Newtonian, Post Minkowskian (PM), Self Force. Among these, Effective Field Theories (EFTs) and quantum amplitudes are used together to extract scattering observables which also have a meaningful classical limit, both in the PM and Self Force frameworks.

We analyse the high energy (Regge) regime of spinless two body scattering within this approach, by the prospect of isolating universal effects and to give insights on the resummation of the PM observables at higher orders, made possible by the simplicity of the calculations in the Regge limit. A sequence of classical Feynman diagrams is recognised to contribute to the leading power and leading log(s/t) in the high energy expansion. We compute them up to four loops (5PM) and use analyticity properties of the S Matrix to maximise the information that we can extract at any PM order.

Locandina_ROSI.docx

Rosi.pdf