Spontaneous Lorentz Violation via QED with Non-Exact Gauge Invariance

TL;DR

This paper explores a modified QED theory where spontaneous Lorentz violation, caused by a vector field vacuum expectation value, leads to observable phenomena such as altered cosmic-ray cutoffs and particle stability, with potential astrophysical implications.

Contribution

It introduces a QED model with tiny gauge non-invariance that makes spontaneous Lorentz violation physically significant, revealing new observable effects.

Findings

Altered GZK cutoff for ultra-high-energy cosmic rays

Stability of high-energy pions and W bosons

Modified nucleon beta decay processes

Abstract

We reconsider an alternative theory of the QED with the photon as a massless vector Nambu-Goldstone boson and show that the underlying spontaneous Lorentz violation caused by the vector field vacuum expectation value, while being superficial in gauge invariant theory, becomes physically significant in the QED with a tiny gauge non-invariance. This leads, through special dispersion relations appearing for charged fermions, to a new class of phenomena which could be of distinctive observational interest in particle physics and astrophysics. They include a significant change in the GZK cutoff for UHE cosmic-ray nucleons, stability of high-energy pions and W bosons, modification of nucleon beta decays, and some others.