Wave packet treatment of neutrino flavor oscillations in various spacetimes

TL;DR

This paper investigates how gravity influences neutrino flavor oscillations when neutrinos are modeled as wave packets in various curved spacetimes, comparing different formalisms and applying them to multiple metrics.

Contribution

It introduces two approaches for wave packet formalism in curved spacetime and applies them to both general relativity and modified gravity metrics.

Findings

Gravity affects neutrino oscillation phases in curved spacetime.

Wave packet formalism provides a more realistic description than plane waves.

Different spacetime metrics yield distinct oscillation behaviors.

Abstract

We study the effect of gravity on neutrino flavor oscillations when each mass eigenstate is described by a wave packet instead of a plane wave. Two different approaches for implementing the wave packet formalism in the study of neutrino flavor oscillations in curved spacetime are examined. We work with a general static and spherically symmetric spacetime before applying our results to a few spacetime metrics of interest. We first focus on general relativity by examining the effect of the exterior and interior Schwarzschild solutions, as well as the de Sitter-Schwarzschild metric, and then we examine selected metrics from modified gravity models.