2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/224247We 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.17 pages, no figures, version to appear in PRDHigh Energy Physics - TheoryGeneral Relativity and Quantum CosmologyNuclear Theorytext