Quantum field theory treatment of neutrino flavor oscillations in matter

TL;DR

This paper develops a quantum field theory approach to neutrino flavor oscillations in matter, deriving exact propagators for Majorana neutrinos and confirming consistency with standard quantum mechanical results.

Contribution

It introduces a quantum field theory framework with exact propagators for neutrinos in matter, providing a more fundamental derivation of oscillation probabilities.

Findings

Exact neutrino propagators in matter derived

Transition probabilities match standard quantum mechanics

Analysis of approximations used in the model

Abstract

We study neutrino oscillations in background matter within the quantum field theory formalism where neutrino mass eigenstates are virtual particles. In this case, neutrino mass eigenstates are mixed owing to the interaction with matter. Assuming that neutrinos are Majorana particles, we find the exact propagators for massive neutrinos accounting for the interaction with matter by solving the analog of the Dyson equation. These propagators are used to calculate the transition probability which coincides with the prediction of the standard quantum mechanical treatment of neutrino flavor oscillations in uniform matter. Finally, we analyze the approximations made in our analysis.