Impact of antiparticle degrees of freedom on neutrino flavor oscillations in frames of quantum field theory

TL;DR

This paper investigates neutrino flavor oscillations within quantum field theory, focusing on the role of antiparticle degrees of freedom and validating the particle contribution approach in vacuum conditions.

Contribution

It provides a rigorous justification for using only particle contributions in neutrino propagator calculations within QFT, extending previous methods.

Findings

Validated the particle contribution approach in vacuum oscillations

Extended the QFT framework to include antiparticle effects

Provided a basis for applying this approach to external field scenarios

Abstract

We study neutrino flavor oscillations using the approach based on the quantum field theory (QFT), where neutrinos are taken to be virtual particles. One deals with the propagators of neutrino mass eigenstates in this formalism. Previously, while applying this approach to neutrino oscillations in external fields, we decomposed the propagators and used only the particle contribution in the calculation of the matrix element. In the present work, we carefully justify the validity of this kind of transformation by considering neutrino oscillations in vacuum. In principle, the results obtained can be extended for the QFT applied to neutrino oscillations in external fields.