Speaker
Description
We discuss a new dissipative fluid theory on an arbitrary (flat or curved) spacetime background. This theory is obtained from kinetic theory by applying a new version of the relativistic Chapman-Enskog method to derive the constitutive relations to first order in the Knudsen parameter. The novelty of our approach consists in applying a suitable projection method to solve the linearized Boltzmann equation and to use the so-called trace-fixed particle frame, which determines the state variables $n$,$T$,$u$ (particle density, temperature parameter and four-velocity) by fixing the trace of the stress-energy tensor in addition to the particle current density. As we show, this leads naturally to a dissipative fluid theory which, in contrast to the traditional first-order theories (Eckart and Landau), is hyperbolic, causal, and stable at global equilibrium configurations.