Coupling constant dependence of the shear viscosity in [formula omitted] supersymmetric Yang–Mills theory

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 YM 2 N c is independent of the coupling and equals to π N 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 / 4 π in the limit of infinite coupling). The correction to 1 / 4 π scales as ( g YM 2 N c ) − 3 / 2 with a positive coefficient.