Entropy current in relativistic quantum statistical mechanics

In this work, we study the entropy production of relativistic quantum fluids at local thermodynamic equilibrium. In particular, we put forward a general method to calculate the entropy current in the framework of relativistic quantum statistical mechanics. We then apply our method to the study of two different systems, both of phenomenological concern in the context of heavy-ion collisions. The first system is a relativistic quantum fluid at global thermodynamic equilibrium with acceleration, whereas the second one is a relativistic quantum fluid with boost invariance. We calculate the thermal expectation value of the energy-momentum tensor, discuss renormalisation and work out the entropy current.