Navier-Stokes limit for a thermal stochastic lattice gas

We study a stochastic particle system on the lattice whose particles move f reely according to a simple exclusion process and change velocities during collisions preserving energy and momentum. In the hydrodynamic limit, under diffusive space-time scaling, the local velocity field u satisfies the inc ompressible Navier-Stokes equation, while the temperature field theta solve s the heat equation with drift Ir. The results are also extended to include a suitably resealed external force.