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Have we already detected astrophysical symptoms of space-time noncommutativity ?

Takashi Tamaki·Tomohiro Harada·Umpei Miyamoto·Takashi Torii
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Abstract

We discuss astrophysical implications of $κ$-Minkowski space-time, in which there appears space-time noncommutativity. We first derive a velocity formula for particles based on the motion of a wave packet. The result is that a massless particle moves at a constant speed as in the usual Minkowski space-time, which implies that an arrival time analysis by $γ$-rays from Markarian (Mk) 421 does not exclude space-time noncommutativity. Based on this observation, we analyze reaction processes in $κ$-Minkowski space-time which are related to the puzzling detections of extremely high-energy cosmic rays above the Greisen-Zatsepin-Kuzmin cutoff and of high-energy ($\sim$20 TeV) $γ$-rays from Mk 501.

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Takashi Tamaki, Tomohiro Harada, Umpei Miyamoto, Takashi Torii. 2001-12-04. Have we already detected astrophysical symptoms of space-time noncommutativity ?. https://doi.org/10.1103/physrevd.65.083003

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