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arXiv · hep-ph/9808446

Evading the GZK Cosmic-Ray Cutoff

Sidney Coleman·Sheldon L. Glashow
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Abstract

Explanations of the origin of ultra-high energy cosmic rays are severely constrained by the Greisen-Zatsepin-Kuz'min effect, which limits their propagation over cosmological distances. We argue that possible departures from strict Lorentz invariance, too small to have been detected otherwise, can affect elementary-particle kinematics so as to suppress or forbid inelastic collisions of cosmic-ray nucleons with background photons. Thereby can the GZK cutoff be relaxed or removed.

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Sidney Coleman, Sheldon L. Glashow. 1998-08-27. Evading the GZK Cosmic-Ray Cutoff. https://arxiv.org/abs/hep-ph/9808446

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