Many-body effects of collective neutrino oscillations

TL;DR

This paper investigates many-body effects in collective neutrino oscillations, revealing deviations from mean-field predictions and highlighting the importance of many-body decoherence in astrophysical phenomena.

Contribution

It provides the first exact solutions for large neutrino systems, demonstrating significant many-body effects absent in mean-field models.

Findings

Quantitative deviation from mean-field evolution due to many-body decoherence

Observation of similar effects in spin-1 Bose-Einstein condensates

Implications for astrophysical neutrino flavor evolution

Abstract

Collective neutrino oscillations are critical to determine the neutrino flavor content, which has striking impacts on core-collapse supernovae or compact binary merger remnants. It is a challenging many-body problem that so far has been mainly studied at the mean-field approximation. We use a setup that captures the relevant physics and allows exact solution for a large number of neutrinos. We, for the first time, find quantitative deviation from the mean-field evolution due to many-body decoherence in flavor space. Similar features have been observed in a spin-1 Bose-Einstein condensate, which opens the possibility of experimental explorations of collective flavor phenomena. Our results call for more careful examinations on the possible many-body corrections to collective neutrino oscillations in astrophysical environments.