1212.0824 (J. Peralta-Ramos et al.)

Macroscopic approximation to relativistic kinetic theory from a
nonlinear closure    [PDF]

J. Peralta-Ramos, E. Calzetta

We use a macroscopic description of a system of relativistic particles based on adding a nonequilibrium tensor to the usual hydrodynamic variables. The nonequilibrium tensor is linked to relativistic kinetic theory through a nonlinear closure suggested by the Entropy Production Principle; the evolution equation is obtained by the method of moments, and together with energy-momentum conservation closes the system. Transport coefficients are chosen to reproduce second order fluid dynamics if gradients are small. Comparison to exact solutions of Boltzmann's equation in 0+1 dimensions shows that the resulting formalism tracks kinetic theory better than second order fluid dynamics. Finally, we discuss an example of application to heavy ion collisions at RHIC energies.

View original: http://arxiv.org/abs/1212.0824