{ "id": "2502.04272", "version": "v1", "published": "2025-02-06T18:14:43.000Z", "updated": "2025-02-06T18:14:43.000Z", "title": "Strong Borel--Cantelli Lemmas for Recurrence", "authors": [ "Tomas Persson", "Alejandro Rodriguez Sponheimer" ], "comment": "22 pages, 3 figures", "categories": [ "math.DS" ], "abstract": "Let $(X,T,\\mu,d)$ be a metric measure-preserving system for which $3$-fold correlations decay exponentially for Lipschitz continuous observables. Suppose that $(M_k)$ is a sequence satisfying some weak decay conditions and suppose there exist open balls $B_k(x)$ around $x$ such that $\\mu(B_k(x)) = M_k$. Under a short return time assumption, we prove a strong Borel--Cantelli lemma, including an error term, for recurrence, i.e., for $\\mu$-a.e. $x \\in X$, \\[ \\sum_{k=1}^{n} \\mathbf{1}_{B_k(x)} (T^k x) = \\Phi(n) + O \\bigl( \\Phi(n)^{1/2} (\\log \\Phi(n))^{3/2 + \\varepsilon} \\bigr), \\] where $\\Phi(n) = \\sum_{k=1}^{n} \\mu(B_k(x))$. Applications to systems include some non-linear piecewise expanding interval maps and hyperbolic automorphisms of $\\mathbf{T}^2$.", "revisions": [ { "version": "v1", "updated": "2025-02-06T18:14:43.000Z" } ], "analyses": { "subjects": [ "37B20", "37D20", "37A05" ], "keywords": [ "strong borel-cantelli lemma", "recurrence", "short return time assumption", "weak decay conditions", "fold correlations decay" ], "note": { "typesetting": "TeX", "pages": 22, "language": "en", "license": "arXiv", "status": "editable" } } }