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arXiv · hep-th/0210220

From AdS/CFT correspondence to hydrodynamics. II. Sound waves

G. Policastro·D. T. Son·A. O. Starinets
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Abstract

As a non-trivial check of the non-supersymmetric gauge/gravity duality, we use a near-extremal black brane background to compute the retarded Green's functions of the stress-energy tensor in N=4 super-Yang-Mills (SYM) theory at finite temperature. For the long-distance, low-frequency modes of the diagonal components of the stress-energy tensor, hydrodynamics predicts the existence of a pole in the correlators corresponding to propagation of sound waves in the N=4 SYM plasma. The retarded Green's functions obtained from gravity do indeed exhibit this pole, with the correct values for the sound speed and the rate of attenuation.

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G. Policastro, D. T. Son, A. O. Starinets. 2005-07-26. From AdS/CFT correspondence to hydrodynamics. II. Sound waves. https://doi.org/10.1088/1126-6708%2F2002%2F12%2F054

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