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

@article{Tamaki2002HaveWA, title={Have we already detected astrophysical symptoms of space-time noncommutativity?}, author={Takashi Tamaki and Tomohiro Harada and Umpei Miyamoto and Takashi Torii}, journal={Physical Review D}, year={2002}, volume={65}, pages={083003} }

We discuss astrophysical implications of $\kappa$-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 $\gamma$-rays from Markarian (Mk) 421 does not exclude space-time noncommutativity. Based on this observation, we analyze reaction… Expand

#### 23 Citations

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