{ "id": "2210.07859", "version": "v1", "published": "2022-10-14T14:30:10.000Z", "updated": "2022-10-14T14:30:10.000Z", "title": "Biased Random Walk on Spanning Trees of the Ladder Graph", "authors": [ "Nina Gantert", "Achim Klenke" ], "comment": "26 pages, 9 figures", "categories": [ "math.PR" ], "abstract": "Consider a two-sided infinite horizontal ladder and pick a random spanning tree with a certain edge weight $c$ for the (vertical) rungs. Now take a random walk on that spanning tree with a bias $\\beta>1$ to the right. We give an explicit formula for the speed of that random walk and show that it is a continuous, unimodal function of $\\beta$ that is positive if and only if $\\beta < \\beta_c^{(1)}$ for an explicit critical value $\\beta_c^{(1)}$ depending on $c$. We also show a central limit theorem for $\\beta< \\beta_c^{(2)} $, for an explicit critical value $\\beta_c^{(2)}$. We see that $\\beta_c^{(2)}$ is smaller than the value of $\\beta$ which achieves the maximal value of the speed. Finally, we confirm the Einstein relation for the unbiased model ($\\beta=1$) by proving a Central Limit Theorem and computing the variance.", "revisions": [ { "version": "v1", "updated": "2022-10-14T14:30:10.000Z" } ], "analyses": { "subjects": [ "60K37", "60G50", "60F05" ], "keywords": [ "biased random walk", "ladder graph", "central limit theorem", "explicit critical value", "two-sided infinite horizontal ladder" ], "note": { "typesetting": "TeX", "pages": 26, "language": "en", "license": "arXiv", "status": "editable" } } }