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arXiv · 1011.5912

Non-universal shear viscosity from Einstein gravity

Johanna Erdmenger·Patrick Kerner·Hansjörg Zeller
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Abstract

A very famous result of gauge/gravity duality is the universality of the ratio of shear viscosity to entropy density in every field theory holographically dual to classical, two-derivative (Einstein) gravity. We present a way to obtain deviation form this universality by breaking the rotational symmetry spontaneously. In anisotropic fluids additional shear modes exist and their corresponding shear viscosities may be non-universal. We confirm this by explicitly calculating the shear viscosities in a transversely isotropic background, a p-wave superfluid, and study its critical behavior. This is a first decisive step towards further applications of gauge/gravity duality to physical systems.

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Johanna Erdmenger, Patrick Kerner, Hansjörg Zeller. 2010-11-26. Non-universal shear viscosity from Einstein gravity. https://doi.org/10.1016/j.physletb.2011.04.009

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