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arXiv · 0712.2451

Relativistic viscous hydrodynamics, conformal invariance, and holography

R. Baier·P. Romatschke·D. T. Son·A. O. Starinets·M. A. Stephanov
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Abstract

We consider second-order viscous hydrodynamics in conformal field theories at finite temperature. We show that conformal invariance imposes powerful constraints on the form of the second-order corrections. By matching to the AdS/CFT calculations of correlators, and to recent results for Bjorken flow obtained by Heller and Janik, we find three (out of five) second-order transport coefficients in the strongly coupled N=4 supersymmetric Yang-Mills theory. We also discuss how these new coefficents can arise within the kinetic theory of weakly coupled conformal plasmas. We point out that the Mueller-Israel-Stewart theory, often used in numerical simulations, does not contain all allowed second-order terms and, frequently, terms required by conformal invariance.

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R. Baier, P. Romatschke, D. T. Son, A. O. Starinets, M. A. Stephanov. 2008-07-15. Relativistic viscous hydrodynamics, conformal invariance, and holography. https://doi.org/10.1088/1126-6708%2F2008%2F04%2F100

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