【摘 要】
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Ultrahigh-energy (UHE) photons up to 1.4 peta-electronvolts have been observed by new cosmic-ray telescope in China [1]-a hint that Lorentz invariance might break down at the Planck-scale level [2].rnAs one of the most sensitive gamma-ray detector arrays
【机 构】
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School of Physics and State Key Laboratory of Nuclear Physics and Technology,Peking University,Beiji
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Ultrahigh-energy (UHE) photons up to 1.4 peta-electronvolts have been observed by new cosmic-ray telescope in China [1]-a hint that Lorentz invariance might break down at the Planck-scale level [2].rnAs one of the most sensitive gamma-ray detector arrays cur-rently operating in the UHE band,the Large High Altitude Air Shower Observatory (LHAASO) recently reported large numbers of gamma-ray photons with energies larger than 100 TeV from twelve cosmic accelerators within the Milky Way [1],including the most high-energetic γ-ray detected at about 1.4 PeV.The observation of such high-energy lights from space can be used not only to investigate the long-lasting puzzle of the origin of UHE cosmic rays and their acceleration mechanism in the extreme regions of the Universe,but can provide also the unique and crucial opportunity in testing fundamental concepts of physics,such as one basic symmetry underlying Einstein\'s relativity-Lorentz invariance [2].
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