Ultra-High Energy Cosmic Rays and Symmetries of Spacetime

O. Bertolami

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arXiv · astro-ph/0012462

Ultra-High Energy Cosmic Rays and Symmetries of Spacetime

O. Bertolami

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Abstract

High energy cosmic rays allow probing phenomena that are inacessible to accelerators. Observation of cosmic rays, presumebly protons, with energies beyond $4 \times 10^{19} eV$, the so-called Greisen-Zatsepin-Kuzmin (GZK) cut-off, give origin to two puzzles: How do particles accelerate to such energies ? Are their sources within $50 - 100 Mpc$ from Earth, or Lorentz invariance is actually a broken symmetry ?

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O. Bertolami. 2001-05-15. Ultra-High Energy Cosmic Rays and Symmetries of Spacetime. https://arxiv.org/abs/astro-ph/0012462

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