A remark on diffusion of directed polymers in random environments
A system of random walks, interpreted as that of directed polymers interacting with a environment which is random in space and time, may with probability one display a diffusive behaviour. Minimal assumptions on the distribution of the environment are established. Precise estimates are obtained for the asymptotics of the mean square displacement of the system in dimensions exceeding two. This generalizes earlier results due to \textit{Y. G. Sinai} [Fundam. Math. 147, No. 2, 173-180 (1995; Zbl 0835.60062)].
scientific article; zbMATH DE number 1279712