Faster-than-c Signals, Special Relativity, and Causality

  title={Faster-than-c Signals, Special Relativity, and Causality},
  author={Stefano Liberati and Sebastiano Sonego and Matt Visser},
  journal={Annals of Physics},
Motivated by the recent attention on superluminal phenomena, we investigate the compatibility between faster-than-c propagation and the fundamental principles of relativity and causality. We first argue that special relativity can easily accommodate—indeed, does not exclude—faster-than-c signaling at the kinematical level. As far as causality is concerned, it is impossible to make statements of general validity, without specifying at least some features of the tachyonic propagation. We thus… 

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