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arXiv · 0810.3475

Limits on an Energy Dependence of the Speed of Light from a Flare of the Active Galaxy PKS 2155-304

H. E. S. S. Collaboration·:·F. Aharonian
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Abstract

In the past few decades, several models have predicted an energy-dependence of the speed of light in the context of quantum gravity. For cosmological sources such as active galaxies, this minuscule effect can add up to measurable photon-energy dependent time lags. In this paper a search for such time lags during the H.E.S.S. observations of the exceptional very high energy flare of the active galaxy PKS 2155-304 on 28 July in 2006 is presented. Since no significant time lag is found, lower limits on the energy scale of speed of light modifications are derived.

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H. E. S. S. Collaboration, :, F. Aharonian. 2008-10-20. Limits on an Energy Dependence of the Speed of Light from a Flare of the Active Galaxy PKS 2155-304. https://doi.org/10.1103/physrevlett.101.170402

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