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arXiv · 0901.1421

Shear Viscosity from Gauss-Bonnet Gravity with a Dilaton Coupling

Rong-Gen Cai·Zhang-Yu Nie·Nobuyoshi Ohta·Ya-Wen Sun
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Abstract

We calculate the shear viscosity of field theories with gravity duals of Gauss-Bonnet gravity with a non-trivial dilaton using AdS/CFT. We find that the dilaton filed has a non-trivial contribution to the ratio of shear viscosity over entropy density and after imposing causal constraint for the boundary field theory, the new lower bound $4/25π$, obtained from pure Gauss-Bonnet gravity, may have a small violation.

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Rong-Gen Cai, Zhang-Yu Nie, Nobuyoshi Ohta, Ya-Wen Sun. 2009-02-27. Shear Viscosity from Gauss-Bonnet Gravity with a Dilaton Coupling. https://doi.org/10.1103/physrevd.79.066004

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