Shear viscosity $\eta$ to electric conductivity $\sigma_{el}$ ratio for the Quark Guon Plasma

Armando Puglisi, Salvatore Plumari, Vincenzo Greco
2015 Proceedings of 53rd International Winter Meeting on Nuclear Physics — PoS(Bormio2015)   unpublished
The transport coefficients of strongly interacting matter are currently subject of intense theoretical and phenomenological studies due to their relevance for the characterization of the quark-gluon plasma produced in ultra-relativistic heavy-ion collisions (uRHIC). We discuss the connection between the shear viscosity to entropy density ratio, η/s, and the electric conductivity, σ el . We note that once the relaxation time is tuned to determine the shear viscosity η to have a minimum value η/s
more » ... = 1/4π near the critical temperature T c , one simultaneously predicts an electric conductivity σ el /T very close to recent lQCD data. More generally, we discuss why the ratio of η/s over σ el /T supplies a measure of the quark to gluon scattering rates whose knowledge would allow to significantly advance in the understanding of the QGP phase. We also predict that (η/s)/(σ el /T ), independently on the running coupling α s (T ), should increase up to about ∼ 20 for T → T c , while it goes down to a nearly flat behavior around 4 for T ≥ 4 T c .
doi:10.22323/1.238.0011 fatcat:usg3qz5wybfwrag452y5ovo6xq