HEP Colloquia 2025

by Domenico Frattulillo (INFN, Sezione di Napoli)

Wednesday 22 Oct 2025, 14:30 → 15:00 Europe/Rome

Sala Consiliare (Department of Physics)

Quantum Gravity Phenomenology: from high energy astrophysics to cold-atom interferometry

In the first part of this talk I will present how astrophysical neutrinos can be used to test in-vacuo dispersion, one of the most studied candidate effects of quantum gravity which predicts an energy dependence of the speed of ultrarelativistic particles.  In particular I will discuss how the failure to observe neutrinos from GRBs could, in principle, be attributed to in-vacuo dispersion that makes neutrinos arrive with an energy dependent delay with respect to their electromagnetic counterparts. Finally, I will also contemplate the possibility that, assuming in-vacuo dispersion, the recently announced ultra-high-energy neutrino 230213A with energy of ∼220 PeV, might be a GRB neutrino.

 

In the second part of the talk I will discuss phenomenological opportunities arising from the deep-infrared regime. In fact, several approaches to quantum gravity predict infrared counterparts to ultraviolet effects due to the so-called IR/UV mixing mechanism. I will discuss how some implications for IR/UV mixing of some recent cold-atom-interferometry measurements allow us to estabilish Planckian bounds on the characteristic quantum-gravity scale, and show that IR/UV mixing can provide a solution to the puzzling discrepancy between cesium- and rubidium-based atom-interferometric determinations of the fine-structure constant.