Neutrino oscillations in a Robertson-Walker Universe with space time foam

TL;DR

This paper extends previous models of neutrino decoherence in fluctuating space-times to include the effects of the expanding universe, assessing the detectability of such effects in high-energy extragalactic neutrinos.

Contribution

It incorporates cosmological expansion into decoherence models for neutrino oscillations, enhancing their relevance for astrophysical observations.

Findings

Decoherence effects are less detectable in models based on string theory foam.

Expansion of the universe influences the magnitude of neutrino decoherence.

Detectability of decoherence effects remains challenging with current experiments.

Abstract

In Phys. Rev. D77 (2008) 105001, we have studied decoherence models for flavour oscillations in four-dimensional stochastically fluctuating space times and discussed briefly the sensitivity of current terrestrial and astrophysical neutrino experiments to such models. In this addendum we extend these results to incorporate the effects due to the expansion of the Universe, so that our analysis can be useful in studies of extragalactic high-energy neutrinos, such as those coming from Gamma Ray Bursts at cosmological distances. Unfortunately for some microscopic models of foam, constructed in the string theory framework, we arrive at pessimistic conclusions about the detectability of the decoherence effects via flavour oscillation meaurements.