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Coupling constant dependence of the shear viscosity in N=4 supersymmetric Yang-Mills theory

Alex Buchel·James T. Liu·Andrei O. Starinets
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Abstract

Gauge theory - gravity duality predicts that the shear viscosity of N=4 supersymmetric SU(N_c) Yang-Mills plasma at temperature T in the limit of large N_c and large 't Hooft coupling g^2_{YM} N_c is independent of the coupling and equals to πN_c^2 T^3/8. In this paper, we compute the leading correction to the shear viscosity in inverse powers of 't Hooft coupling using the α'-corrected low-energy effective action of type IIB string theory. We also find the correction to the ratio of shear viscosity to the volume entropy density (equal to 1/4πin the limit of infinite coupling). The correction to 1/4πscales as (g^2_{YM} N_c)^{-3/2} with a positive coefficient.

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Alex Buchel, James T. Liu, Andrei O. Starinets. 2007-07-11. Coupling constant dependence of the shear viscosity in N=4 supersymmetric Yang-Mills theory. https://doi.org/10.1016/j.nuclphysb.2004.11.055

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