Nonextensive hydrodynamics for relativistic heavy-ion collisions

Abstract

The nonextensive one-dimensional version of a hydrodynamic model for multiparticle production processes is proposed and discussed. It is based on nonextensive statistics assumed in the form proposed by Tsallis and characterized by a nonextensivity parameter $q$. In this formulation, the parameter $q$ describes some specific form of local equilibrium that is characteristic of the nonextensive thermodynamics and replaces the local thermal equilibrium assumption of the usual hydrodynamic models. We argue that there is correspondence between the perfect nonextensive hydrodynamics and the usual dissipative hydrodynamics. It leads to a simple expression for dissipative entropy current and allows predictions of the ratio of bulk and shear viscosities to entropy density, $\ensuremath{\zeta}/s$ and $\ensuremath{\eta}/s$, to be made.