Time Correlation Functions from the Boltzmann Equation

It is shown that the nonlinear Boltzmann equation, as opposed to its linearized version, predicts time correlation functions with asymptotic tails $\simeq c{t}^{-\frac{3}{2}}$, and with coefficients $c$ in agreement with recently obtained results. The appropriate specialization of the mode-mode formula is also shown to follow from the nonlinear Boltzmann equation.