{ "id": "2105.05219", "version": "v2", "published": "2021-05-11T17:35:18.000Z", "updated": "2021-06-13T20:47:58.000Z", "title": "Sharp phase transition for Gaussian percolation in all dimensions", "authors": [ "Franco Severo" ], "comment": "19 pages", "categories": [ "math.PR", "math-ph", "math.MP" ], "abstract": "We consider the level-sets of continuous Gaussian fields on $\\mathbb{R}^d$ above a certain level $-\\ell\\in \\mathbb{R}$, which defines a percolation model as $\\ell$ varies. We assume that the covariance kernel satisfies certain regularity, symmetry and positivity conditions as well as a polynomial decay with exponent greater than $d$ (in particular, this includes the Bargmann-Fock field). Under these assumptions, we prove that the model undergoes a sharp phase transition around its critical point $\\ell_c$. More precisely, we show that connection probabilities decay exponentially for $\\ell<\\ell_c$ and percolation occurs in sufficiently thick 2D slabs for $\\ell>\\ell_c$. This extends results recently obtained in dimension $d=2$ to arbitrary dimensions through completely different techniques. The result follows from a global comparison with a truncated (i.e. with finite range of dependence) and discretized (i.e. defined on the lattice $\\varepsilon\\mathbb{Z}^d$) version of the model, which may be of independent interest. The proof of this comparison relies on an interpolation scheme that integrates out the long-range and infinitesimal correlations of the model while compensating them with a slight change in the parameter $\\ell$.", "revisions": [ { "version": "v2", "updated": "2021-06-13T20:47:58.000Z" } ], "analyses": { "subjects": [ "82B43", "60K35", "60G15", "60G60" ], "keywords": [ "sharp phase transition", "gaussian percolation", "connection probabilities decay", "covariance kernel satisfies", "sufficiently thick 2d slabs" ], "note": { "typesetting": "TeX", "pages": 19, "language": "en", "license": "arXiv", "status": "editable" } } }