Anomalous self-diffusion for one-dimensional hard cores

The time-displaced self-correlation function for a one-dimensional hard-core fluid with independent stochastic forces acting on each core is solved exactly and concisely. At long time, the distribution has a spread given by δx(t)=[R(t)n]12, where R(t) is the absolute dispersion in position of a noninteracting particle and n the free-volume reduced density. The diffusional behavior without stochastic background, and non-Fickian diffusion of Levitt with Brownian background, are reproduced.