Article

# Relativistic viscous hydrodynamics, conformal invariance, and holography

• ##### M. A. Stephanov
Journal of High Energy Physics (Impact Factor: 5.62). 04/2008; 2008(04):100. DOI: 10.1088/1126-6708/2008/04/100
Source: arXiv

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 = 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 Müller-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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