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arXiv · hep-th/0309213

Holography and hydrodynamics: diffusion on stretched horizons

Pavel Kovtun·Dam T. Son·Andrei O. Starinets
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Abstract

We show that long-time, long-distance fluctuations of plane-symmetric horizons exhibit universal hydrodynamic behavior. By considering classical fluctuations around black-brane backgrounds, we find both diffusive and shear modes. The diffusion constant and the shear viscosity are given by simple formulas, in terms of metric components. For a given metric, the answers can be interpreted as corresponding kinetic coefficients in the holographically dual theory. For the near-extremal Dp, M2 and M5 branes, the computed kinetic coefficients coincide with the results of independent AdS/CFT calculations. In all the examples, the ratio of shear viscosity to entropy density is equal to \hbar/(4πk_B), suggesting a special meaning of this value.

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Pavel Kovtun, Dam T. Son, Andrei O. Starinets. 2003-09-23. Holography and hydrodynamics: diffusion on stretched horizons. https://doi.org/10.1088/1126-6708%2F2003%2F10%2F064

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