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arXiv · 0912.2100

Notes on the bulk viscosity of holographic gauge theory plasmas

Amos Yarom
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Abstract

A novel technique is used to compute the bulk viscosity of high temperature holographic gauge theory plasmas with softly broken conformal symmetry. Working in a black hole background which corresponds to a non-trivial solution to the Navier-Stokes equation, and using a Ward identity for the trace of the stress-energy tensor, it is possible to obtain an analytic expression for the bulk viscosity. This can be used to verify the high temperature limit of a conjectured bound on the bulk viscosity for these theories. The bound is saturated when the conformal symmetry-breaking operator becomes marginal.

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Amos Yarom. 2009-12-10. Notes on the bulk viscosity of holographic gauge theory plasmas. https://doi.org/10.1007/jhep04(2010)024

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