Journal of Statistical Physics, Vol. 50, Nos. 3/4, 1988. p. 611-632.
Proof is given of the existence of a classical solution to the nonlinear Boltzmann equation in all R^3. The solution, which is global in time, exists if the initial data go to zero fast enough at infinity and the mean free path is sufficiently large. The solution is smooth in the space variable if the initial value is smooth. The asymptotic behavior of solutions is also given. It is shown that as t -> oo the solution to the Boltzrnann equation can be approximated by the solution to the free motion problem.