Speed Variations of Cosmic Photons and Neutrinos from Loop Quantum Gravity

Hao Li; Bo-Qiang Ma

doi:10.1016/j.physletb.2022.137613

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arXiv · 2212.04220

Speed Variations of Cosmic Photons and Neutrinos from Loop Quantum Gravity

Hao Li·Bo-Qiang Ma

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Abstract

Recently a series of analyses on the flight time of cosmic photons and neutrinos suggests that the speed of light \emph{in vacuo} takes the energy-dependent form $v(E)\simeq 1-E/E_{\text{LIV}}^{γ}$ with $E_{\text{LIV}}^{γ}\approx 3.6\times 10^{17}~\text{GeV}$, and meanwhile the speed of neutrinos is proposed to be $v(E)\simeq 1\pm E/E_{\text{LIV}}^{ν}$ with $E_{\text{LIV}}^{ν}\approx 6.5\times 10^{17}~\text{GeV}$ and $\pm {}$ representing the helicity dependence. This novel picture immediately urges us to provide a satisfactory theoretical explanation. Among all the attempts to predict the speed variations from quantum gravity, we find that loop quantum gravity can serve as a good candidate for explaining the aforementioned picture consistently.

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Hao Li, Bo-Qiang Ma. 2022-12-13. Speed Variations of Cosmic Photons and Neutrinos from Loop Quantum Gravity. https://doi.org/10.1016/j.physletb.2022.137613

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