Can we see quantum gravity? Photons in the asymptotic-safety scenario

TL;DR

This paper explores the potential for experimental detection of quantum gravity effects through photon-photon scattering in asymptotically safe quantum gravity models with extra dimensions, suggesting near-future collider experiments could observe these effects.

Contribution

It proposes that photon-photon scattering experiments at upcoming colliders could serve as a first observational window into quantum gravity within the asymptotic safety framework.

Findings

Photon-photon scattering can reveal quantum gravity effects.

Near-future collider setups may detect quantum gravitational phenomena.

Extra dimensions enhance the observability of quantum gravity effects.

Abstract

In the search for a quantum theory of gravity it is crucial to find experimental access to quantum gravitational effects. Since these are expected to be very small at observationally accessible scales it is advantageous to consider processes with no tree-level contribution in the Standard Model, such as photon-photon scattering. We examine the implications of asymptotically safe quantum gravity in a setting with extra dimensions for this case, and point out that various near-future photon-collider setups, employing either electron or muon colliders, or even a purely laser-based setup, could provide a first observational window into the quantum gravity regime.