{ "id": "2212.00958", "version": "v1", "published": "2022-12-02T03:59:49.000Z", "updated": "2022-12-02T03:59:49.000Z", "title": "A local central limit theorem for random walks on expander graphs", "authors": [ "Rafael Chiclana", "Yuval Peres" ], "comment": "13 pages, 0 figures", "categories": [ "math.PR" ], "abstract": "On a regular graph $G=(V,E)$, consider a function $\\operatorname{val} \\colon V \\longrightarrow \\{0,1\\}$ that labels the vertices of $G$, and let $(X_i)$ be the simple random walk on $G$ started from a vertex chosen uniformly at random. In this work, we show that the Hamming weight of the sequence of bits $(\\operatorname{val}(X_i))$ satisfies a local central limit theorem when the graph $G$ is expander. As a consequence, we study the pseudorandomness of random walks on expander graphs against test computed by symmetric functions $f\\colon \\{0,1\\}^t \\longrightarrow \\{0,1\\}$. We also show that the Hamming weight of $(\\operatorname{val}(X_i))$ has the same asymptotic behavior as the Hamming weight of the sticky random walk.", "revisions": [ { "version": "v1", "updated": "2022-12-02T03:59:49.000Z" } ], "analyses": { "subjects": [ "05C81", "05C48" ], "keywords": [ "local central limit theorem", "expander graphs", "hamming weight", "sticky random walk", "simple random walk" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable" } } }