c is the speed of light, isn’t it?

  title={c is the speed of light, isn’t it?},
  author={George F R Ellis and Jean-Philippe Uzan},
  journal={American Journal of Physics},
  • G. Ellis, J. Uzan
  • Published 27 May 2003
  • Physics, Education
  • American Journal of Physics
Theories for a varying speed of light have been proposed as an alternative way of solving several standard cosmological problems. Recent observational hints that the fine structure constant may have varied over cosmological scales have given impetus to these theories. However, the speed of light is hidden in many physics equations and plays different roles in them. We discuss these roles to shed light on proposals for varying speed of light theories. We also emphasize the requirements for… 
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