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On the spontaneous breaking of Lorentz invariance

O. Bertolami
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Abstract

We show that estimates of the Lorentz symmetry violation extracted from ultra-high energy cosmic rays beyond the GZK cut-off set bounds on the parameters of a Lorentz-violating extension of the Standard Model. Moreover, we argue that correlated measurements of the difference in the arrival time of gamma-ray photons and neutrinos emitted from Active Galactic Nuclei or Gamma-Ray Bursts may provide a signature for a possible violation of the Lorentz symmetry. We find that this time delay is energy independent, but that it has a dependence on the chirality of the particles involved.

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O. Bertolami. 2000-01-28. On the spontaneous breaking of Lorentz invariance. https://doi.org/10.1016/s0920-5632(00)00753-2

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