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arXiv · 2502.14927

LQG-modified dispersion relations and the problem of cosmic photons threshold anomalies

P. A. L. Mourão·G. L. L. W. Levy·J. A. Helayël-Neto
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Abstract

Our present contribution sets out to investigate how combined effects of Lorentz invariance violation (LIV) and loop quantum gravity (LQG)-modified photon dispersion relations affect the threshold anomaly of cosmic photons. The point of departure is the post-Maxwellian version of electromagnetism induced by LQG effects. We then consider the problem of gamma-ray attenuation by the extragalactic background light (EBL) and the cosmic microwave background radiation (CMB) dominated by the Breit-Wheeler Effect. By following this path, we aim at the establishment of a new bridge between LIV and astrophysical phenomena in the framework of LQG, providing a robust explanation for recent ultra high energy (UHE) astrophysical observations.

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P. A. L. Mourão, G. L. L. W. Levy, J. A. Helayël-Neto. 2025-02-20. LQG-modified dispersion relations and the problem of cosmic photons threshold anomalies. https://arxiv.org/abs/2502.14927

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