Gabriel Soares Rocha

Vanderbilt University, November 10, 12:00 pm

First order relativistic dissipative hydrodynamic theories from Kinetic Theory

The study of heavy ion collisions has stimulated research on the emergence of relativistic dissipative fluid dynamics from a microscopic theory and its domain of applicability. In particular, hydrodynamic theories can be derived employing relativistic Kinetic Theory as the microscopic formalism. In this context, the Chapman-Enskog procedure leads to the traditional Navier-Stokes (NS) theory. However, NS is acausal and unstable in the relativistic regime. Usually hydrodynamic models in heavy ion collisions employ Israel-Stewart-like formalisms for the evolution of the quark-gluon plasma. They are conditionally causal and stable, but present a complex PDE structure. Recently, Bemfica-Disconzi-Noronha-Kovtun (BDNK) has been proposed. BDNK theory possesses similarities with NS, but the employment of alternative definitions of the local equilibrium state and the presence of time-like derivatives in the constitutive relations are essential render it causal, linearly stable, and strongly hyperbolic. In this talk, we shall discuss the Chapman-Enskog procedure and the modified Chapman-Enskog procedure to derive BDNK, presenting some results in toy-models used in Heavy-Ions collisions as an application.