Relativity: Testing times in space

@article{Lamoreaux2002RelativityTT,
  title={Relativity: Testing times in space},
  author={Steve Keith Lamoreaux},
  journal={Nature},
  year={2002},
  volume={416},
  pages={803-804}
}
We take for granted that physical 'constants', such as the speed of light, are fixed values. But they might not be, and experiments in space may allow us to investigate this possibility. 
4 Citations
High-energy cosmic rays and tests of basic principles of Physics. Looking at the Planck scale and beyond
With the present understanding of data, the observed flux suppression for ultra-high energy cosmic rays (UHECR) at energies above 4.10E19 eV can be a signature of the Greisen-Zatsepin-Kuzmin (GZK)
Ultra-high energy physics and standard basic principles - Do Planck units really make sense?
It has not yet been elucidated whether the observed flux suppression for ultra- high energy cosmic rays (UHECR) at energies above � 4x1 0 19 eV is a signature of the Greisen-Zatsepin-Kuzmin (GZK)
Ultra-high energy physics and standard basic principles
It has not yet been elucidated whether the observed flux suppression for ultrahigh energy cosmic rays (UHECR) at energies above 4 x 1019 eV is a signature of the Greisen-Zatsepin-Kuzmin (GZK) cutoff

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