The viscosity bound in string theory
نویسندگان
چکیده
The ratio of shear viscosity to entropy density η/s of any material in nature has been conjectured to have a lower bound of 1/4π, the famous KSS bound. We examine string theory models for evidence in favour of and against this conjecture. We show that in a broad class of models quantum corrections yield values of η/s just above the KSS bound. However, incorporating matter fields in the fundamental representation typically leads to violations of this bound. We also outline a program to extend AdS/CFT methods to RHIC phenomenology. Based on a talk given by AS at Quark Matter 2009, March 30 April 4, Knoxville, Tennessee.
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