Proof of a Universal Lower Bound on the Shear Viscosity to Entropy Density Ratio

@inproceedings{Brustein2009ProofOA,
  title={Proof of a Universal Lower Bound on the Shear Viscosity to Entropy Density Ratio},
  author={Ram Brustein and A. J. M. Medved},
  year={2009}
}
It has been conjectured, on the basis of the gauge-gravity duality, that the ratio of the shear viscosity to the entropy density should be universally bounded from below by 1/4π in units of the Planck constant divided by the Boltzmann constant. Here, we prove the bound for any ghost-free extension of Einstein gravity and the field-theory dual thereof. Our… CONTINUE READING