Relativistic second-order dissipative hydrodynamics at finite chemical potential

Understand

Starting from the Boltzmann equation in the relaxation time approximation and employing a Chapman-Enskog like expansion for the distribution function close to equilibrium, we derive second-order evolution equations for the shear stress tensor and the dissipative charge current for a system of massless quarks and gluons.

• The transport coefficients are obtained exactly using quantum statistics for the phase space distribution functions at non-zero chemical potential.
• We show that, within the relaxation time approximation, the second-order evolution equations for the shear stress tensor and the dissipative charge current can be decoupled.
• We find that, for large values of the ratio of chemical potential to temperature, the charge conductivity is small compared to the coefficient of shear viscosity.