A quenched limit theorem for the local time of random walks on Z
نویسندگان
چکیده
Abstract Let X and Y be two independent random walks on Z with zero mean and finite variances, and let Lt(X,Y ) be the local time of X −Y at the origin at time t. We show that almost surely with respect to Y , Lt(X,Y )/ log t conditioned on Y converges in distribution to an exponential random variable with the same mean as the distributional limit of Lt(X,Y )/ log t without conditioning. This question arises naturally from the study of the parabolic Anderson model with a single moving catalyst, which is closely related to a pinning model.
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