Shear Viscosity from Gauss-Bonnet Gravity with a Dilaton Coupling
نویسندگان
چکیده
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. Email: [email protected] Email: [email protected] Email: [email protected] Email: [email protected]
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