Coincidence of Lyapunov Exponents for Random Walks in Weak Random Potentials
نویسنده
چکیده
We investigate the free energy of nearest-neighbor random walks on Z d , endowed with a drift along the first axis and evolving in a nonnegative random potential given by i.i.d. random variables. Our main result concerns the ballistic regime in dimensions d ≥ 4, at which we show that quenched and annealed Lyapunov exponents are equal as soon as the strength of the potential is small enough.
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