{ "id": "1403.1274", "version": "v2", "published": "2014-03-05T21:15:27.000Z", "updated": "2014-03-07T05:27:33.000Z", "title": "Almost optimal sparsification of random geometric graphs", "authors": [ "Nicolas Broutin", "Luc Devroye", "Gabor Lugosi" ], "categories": [ "math.PR", "cs.DM", "cs.NI", "math.CO" ], "abstract": "A random geometric irrigation graph $\\Gamma_n(r_n,\\xi)$ has $n$ vertices identified by $n$ independent uniformly distributed points $X_1,\\ldots,X_n$ in the unit square $[0,1]^2$. Each point $X_i$ selects $\\xi_i$ neighbors at random, without replacement, among those points $X_j$ ($j\\neq i$) for which $\\|X_i-X_j\\| < r_n$, and the selected vertices are connected to $X_i$ by an edge. The number $\\xi_i$ of the neighbors is an integer-valued random variable, chosen independently with identical distribution for each $X_i$ such that $\\xi_i$ satisfies $1\\le \\xi_i \\le \\kappa$ for a constant $\\kappa>1$. We prove that when $r_n = \\gamma_n \\sqrt{\\log n/n}$ for $\\gamma_n \\to \\infty$ with $\\gamma_n =o(n^{1/6}/\\log^{5/6}n)$, then the random geometric irrigation graph experiences explosive percolation in the sense that when $\\mathbf E \\xi_i=1$, then the largest connected component has size $o(n)$ but if $\\mathbf E \\xi_i >1$, then the size of the largest connected component is with high probability $n-o(n)$. This offers a natural non-centralized sparsification of a random geometric graph that is mostly connected.", "revisions": [ { "version": "v2", "updated": "2014-03-07T05:27:33.000Z" } ], "analyses": { "subjects": [ "05C80", "60C05" ], "keywords": [ "random geometric graph", "optimal sparsification", "random geometric irrigation graph experiences", "largest connected component", "irrigation graph experiences explosive percolation" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1403.1274B" } } }