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تسجيل مستخدم جديدLHAASO discovery of highest-energy photons towards new physics
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Ultrahigh-energy photons up to 1.4 peta-electronvolts have been observed by new cosmic-ray telescope in China -- a hint that Lorentz invariance might break down at the Planck-scale level.
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From special relativity, photon annihilation process HepProcess{{Pgg}{Pgg}{to}{Pep}{Pem}} prevents cosmic photons with energies above a threshold to propagate a long distance in cosmic space due to their annihilation with low energy cosmic background
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