Lorentz violation and perpetual motion

  title={Lorentz violation and perpetual motion},
  author={Christopher Eling and Brendan Z. Foster and Ted Jacobson and Aron C. Wall},
  journal={Physical Review D},
We show that any Lorentz-violating theory with two or more propagation speeds is in conflict with the generalized second law of black hole thermodynamics. We do this by identifying a classical energy-extraction method, analogous to the Penrose process, which would decrease the black hole entropy. Although the usual definitions of black hole entropy are ambiguous in this context, we require only very mild assumptions about its dependence on the mass. This extends the result found by Dubovsky and… Expand
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