{ "id": "math/0206132", "version": "v1", "published": "2002-06-12T21:55:25.000Z", "updated": "2002-06-12T21:55:25.000Z", "title": "Sharp Metastability Threshold for Two-Dimensional Bootstrap Percolation", "authors": [ "Alexander E. Holroyd" ], "categories": [ "math.PR", "math-ph", "math.MP" ], "abstract": "In the bootstrap percolation model, sites in an $L$ by $L$ square are initially independently declared active with probability $p$. At each time step, an inactive site becomes active if at least two of its four neighbours are active. We study the behaviour as $p \\to 0$ and $L \\to \\infty$ simultaneously of the probability $I(L,p)$ that the entire square is eventually active. We prove that $I(L,p) \\to 1$ if $\\liminf p \\log L > \\lambda$, and $I(L,p) \\to 0$ if $\\limsup p \\log L < \\lambda$, where $\\lambda = \\pi^2/18$. We prove the same behaviour, with the same threshold $\\lambda$, for the probability $J(L,p)$ that a site is active by time $L$ in the process on the infinite lattice. The same results hold for the so-called modified bootstrap percolation model, but with threshold $\\lambda' = \\pi^2/6$. The existence of the thresholds $\\lambda,\\lambda'$ settles a conjecture of Aizenman and Lebowitz, while the determination of their values corrects numerical predictions of Adler, Stauffer and Aharony.", "revisions": [ { "version": "v1", "updated": "2002-06-12T21:55:25.000Z" } ], "analyses": { "subjects": [ "60K35", "82B43" ], "keywords": [ "sharp metastability threshold", "two-dimensional bootstrap percolation", "probability", "values corrects numerical predictions", "modified bootstrap percolation model" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2002math......6132H" } } }