Shear viscosity of strongly coupled N=4 supersymmetric Yang-Mills plasma
20 Aug 2001-Physical Review Letters (The American Physical Society)-Vol. 87, Iss: 8, pp 081601-081601
TL;DR: In this article, the authors derived the shear viscosity of the finite-temperature N = 4 supersymmetric Yang-Mills theory in the large N, strong-coupling regime with the absorption cross section of low-energy gravitons by a near-extremal black three-brane.
Abstract: Using the anti–de Sitter/conformal field theory correspondence, we relate the shear viscosity ? of the finite-temperature N = 4 supersymmetric Yang-Mills theory in the large N, strong-coupling regime with the absorption cross section of low-energy gravitons by a near-extremal black three-brane. We show that in the limit of zero frequency this cross section coincides with the area of the horizon. From this result we find ? = ? / 8N2T3. We conjecture that for finite ’t Hooft coupling gYM2N the shear viscosity is ? = f(gYM2N)N2T3, where f(x) is a monotonic function that decreases from O(x-2ln-1(1/x)) at small x to ?/8 when x??.
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