{ "id": "1311.5369", "version": "v2", "published": "2013-11-21T11:21:35.000Z", "updated": "2015-06-19T07:30:38.000Z", "title": "Branching random walks and multi-type contact-processes on the percolation cluster of ${\\mathbb{Z}}^{d}$", "authors": [ "Daniela Bertacchi", "Fabio Zucca" ], "comment": "Published at http://dx.doi.org/10.1214/14-AAP1040 in the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org)", "journal": "Annals of Applied Probability 2015, Vol. 25, No. 4, 1993-2012", "doi": "10.1214/14-AAP1040", "categories": [ "math.PR" ], "abstract": "In this paper we prove that, under the assumption of quasi-transitivity, if a branching random walk on ${{\\mathbb{Z}}^d}$ survives locally (at arbitrarily large times there are individuals alive at the origin), then so does the same process when restricted to the infinite percolation cluster ${{\\mathcal{C}}_{\\infty}}$ of a supercritical Bernoulli percolation. When no more than $k$ individuals per site are allowed, we obtain the $k$-type contact process, which can be derived from the branching random walk by killing all particles that are born at a site where already $k$ individuals are present. We prove that local survival of the branching random walk on ${{\\mathbb{Z}}^d}$ also implies that for $k$ sufficiently large the associated $k$-type contact process survives on ${{\\mathcal{C}}_{\\infty}}$. This implies that the strong critical parameters of the branching random walk on ${{\\mathbb{Z}}^d}$ and on ${{\\mathcal{C}}_{\\infty}}$ coincide and that their common value is the limit of the sequence of strong critical parameters of the associated $k$-type contact processes. These results are extended to a family of restrained branching random walks, that is, branching random walks where the success of the reproduction trials decreases with the size of the population in the target site.", "revisions": [ { "version": "v1", "updated": "2013-11-21T11:21:35.000Z", "title": "Branching random walks and multi-type contact-processes on the percolation cluster of $\\mathbb{Z}^d$", "abstract": "In this paper we prove that under the assumption of quasi-transitivity, if a branching random walk on $\\mathbb{Z}^d$ survives locally (at arbitrarily large times there are individuals alive at the origin), then so does the same process when restricted to the infinite percolation cluster $\\mathcal{C}_\\infty$ of a supercritical Bernoulli percolation. When no more than $k$ individuals per site are allowed, we obtain the $k$-type contact process, which can be derived from the branching random walk by killing all particles that are born at a site where already $k$ individuals are present. We prove that local survival of the branching random walk on $\\mathbb{Z}^d$ also implies that for $k$ sufficiently large the associated $k$-type contact process survives on $\\mathcal{C}_\\infty$. This implies that the strong critical parameters of the branching random walk on $\\mathbb{Z}^d$ and on $\\mathcal{C}_\\infty$ coincide and that their common value is the limit of the sequence of strong critical parameters of the associated $k$-type contact processes. These results are extended to a family of restrained branching random walks, that is branching random walks where the success of the reproduction trials decreases with the size of the population in the target site.", "comment": "13 pages, 6 figures", "journal": null, "doi": null }, { "version": "v2", "updated": "2015-06-19T07:30:38.000Z" } ], "analyses": { "subjects": [ "60K35", "60K37" ], "keywords": [ "branching random walk", "multi-type contact-processes", "strong critical parameters", "type contact process survives", "individuals" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 13, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1311.5369B" } } }