Can light signals travel faster than c in nontrivial vacua in flat space-time? Relativistic causality II

  title={Can light signals travel faster than c in nontrivial vacua in flat space-time? Relativistic causality II},
  author={Heidi Fearn},
  journal={Laser Physics},
  • H. Fearn
  • Published 1 May 2007
  • Physics
  • Laser Physics
In this paper, we show that the Scharnhorst effect (vacuum with boundaries or a Casimir-type vacuum) cannot be used to generate signals showing measurable faster-than-c speeds. Furthermore, we aim to show that the Scharnhorst effect would violate special relativity, by allowing for a variable speed of light in a vacuum, unless one can specify a small invariant length scale. This invariant length scale would be agreed upon by all inertial observers. We hypothesize the approximate scale of the… 


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