Is there a signal for Lorentz non-invariance in existing radioactive decay data?

TL;DR

This paper investigates annual periodicities in radioactive decay rates, proposing they may be caused by neutrino propagation effects related to Lorentz non-invariance or interactions with cosmic particles.

Contribution

It introduces a novel explanation linking decay rate periodicities to neutrino medium effects possibly due to Lorentz non-invariance or cosmic interactions.

Findings

Decay rates show annual periodicities across different nuclei.

A neutrino medium with a varying refractive index could explain these periodicities.

Implications for neutrino mass measurements and fundamental physics.

Abstract

Measurements of the beta decay rates of nuclei have revealed annual periodicities with approximately the same relative amplitude even though the half-lives range over nine orders of magnitude. Here we show that this can be explained if the emitted neutrinos behave as if they propagate in a medium with a refractive index which varies as the Earth orbits the sun. This refractive index may be due to fundamental Lorentz non-invariance (LNI), or apparent LNI arising from interactions with solar or relic neutrinos, or dark matter. Additionally, this medium could have consequences for experiments attempting to measure the neutrino mass.