Beta-Decay Spectrum and Lorentz Violation

TL;DR

This paper explores how precision beta-decay experiments, especially KATRIN, can test Lorentz and CPT invariance, including challenging countershaded departures, potentially leading to the first experimental detection of such symmetry violations in neutrinos.

Contribution

It demonstrates that KATRIN can effectively test for countershaded Lorentz and CPT violations in neutrinos, a previously difficult-to-detect class of symmetry breaking.

Findings

KATRIN can probe countershaded Lorentz violations in neutrinos.

Beta-decay experiments are sensitive to symmetry violations across energy scales.

First experimental search for countershaded Lorentz and CPT breaking in neutrinos is feasible.

Abstract

Relativity theory and its underlying Lorentz and CPT invariance represent key principles of physics and therefore require continued experimental scrutiny across the broadest possible range of energy scales and physical systems. Possibilities for tests of these symmetries in precision $\beta$-decay experiments with focus on KATRIN are investigated. It is found that countershaded departures from relativity, which represent a particular challenge to detection, are accessible in such experiments. In this context, it is argued that KATRIN would be in an excellent position to conduct the first-ever experimental search for countershaded Lorentz and CPT breaking in neutrinos.