Equation of state and viscosities from a gravity dual of the gluon plasma

Employing new precision data of the equation of state of the SU(3) Yang–Mills theory (gluon plasma) the dilaton potential of a gravity-dual model is adjusted in the temperature range (1–10)Tc(1–10)Tc within a bottom-up approach. The ratio of bulk viscosity to shear viscosity follows then as ζ/η≈πΔvs2 for Δvs2<0.2 and achieves a maximum value of 0.94 at Δvs2≈0.3, where Δvs2≡1/3−vs2 is the non-conformality measure and vs2 is the velocity of sound squared, while the ratio of shear viscosity to entropy density is known as (4π)−1(4π)−1 for the considered set-up with Hilbert action on the gravity side.