TRANSIENT RANDOM WALKS ON 2D-ORIENTED LATTICES

We study the asymptotic behavior of the simple random walk on oriented versions of Z(2). The considered lattices are not directed on the vertical axis but unidirectional on the horizontal one, with random orientations whose distributions are generated by a dynamical system. We find a sufficient condition on the smoothness of the generation for the transience of the simple random walk on almost every such oriented lattices, and as an illustration we provide a wide class of examples of inhomogeneous or correlated distributions of the orientations. For ergodic dynamical systems, we also prove a strong law of large numbers and, in the particular case of independent identically distributed orientations, we solve an open problem and prove a functional limit theorem in the space D([ 0, infinity[, R-2) of cadlag functions, with an unconventional normalization.