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تسجيل مستخدم جديدLimit behaviour of random walks on $mathbb Z^m$ with two-sided membrane
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We study Markov chains on $mathbb Z^m$, $mgeq 2$, that behave like a standard symmetric random walk outside of the hyperplane (membrane) $H={0}times mathbb Z^{m-1}$. The transition probabilities on the membrane $H$ are periodic and also depend on the incoming direction to $H$, what makes the membrane $H$ two-sided. Moreover, sliding along the membrane is allowed. We show that the natural scaling limit of such Markov chains is a $m$-dimensional diffusion whose first coordinate is a skew Brownian motion and the other $m-1$ coordinates is a Brownian motion with a singular drift controlled by the local time of the first coordinate at $0$. In the proof we utilize a martingale characterization of the Walsh Brownian motion and determine the effective permeability and slide direction. Eventually, a similar convergence theorem is established for the one-sided membrane without slides and random iid transition probabilities.
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