SPACETIME WITHOUT REFERENCE FRAMES - AN APPLICATION TO THE KINETIC-THEORY

Spacetime structures defined in the language of manifolds admit an abs olute formulation, i.e., a formulation which does not refer to observe rs (reference frames). We consider an affine structure for Galilean sp acetime. As an application the Chapman-Enskog iteration for the soluti on of the Boltzmann equation is given in an absolute form. As a conseq uence, the second approximations of the stress tensor and the heat flu x are obtained in a form independent of observers, which throws new li ght on material frame indifference.