Neutrinos as possible probes for quantum gravity

Abstract

In this paper, we aim to explore the interplay between neutrinos and quantum gravity, illustrating some proposals about the use of these particles as probes for the supposed quantized structure of spacetime. The residual signatures of a more fundamental theory of quantum gravity can manifest themselves modifying the free particle dispersion relations and the connected velocity. In neutrino sector these supposed effects can modify the time of flight for astrophysical particles with different energies and can affect the usual neutrino oscillation pattern introducing species depending perturbations. We will highlight how perturbations caused by non-standard interactions in the solar neutrino sector can mimic the presumed quantum gravity effects. In fact, the mathematical formulation of non-standard interactions is equivalent to that of CPT-odd perturbations. We will, therefore, emphasize the need to identify the nature of different contributions in order to disentangle them in the search for quantum gravity effects. As a final point we will discuss the possibility to detect in the neutrino sector decoherence effects caused by the quantum gravity supposed perturbations. By reviewing current experimental constraints and observations, we seek to shed light on the intricate relationship between neutrinos and quantum gravity, and discuss the challenges and future directions in this fascinating field of research.