Proof of a universal lower bound on the shear viscosity to entropy density ratio
نویسندگان
چکیده
منابع مشابه
Proof of a Universal Lower Bound on the Shear Viscosity to Entropy Density Ratio
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 proof is based on the fact that, for su...
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ژورنال
عنوان ژورنال: Physics Letters B
سال: 2010
ISSN: 0370-2693
DOI: 10.1016/j.physletb.2010.06.018