Shear Viscosity from Gauss-Bonnet Gravity with a Dilaton Coupling
arXiv:0901.1421 · doi:10.1103/PhysRevD.79.066004
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 $4/25Ï$, obtained from pure Gauss-Bonnet gravity, may have a small violation.
17 pages, no figures, version to appear in PRD