{ "id": "1507.01277", "version": "v1", "published": "2015-07-05T21:35:59.000Z", "updated": "2015-07-05T21:35:59.000Z", "title": "Conditional speed of branching Brownian motion, skeleton decomposition and application to random obstacles", "authors": [ "Mehmet Öz", "Mine Çağlar", "János Engländer" ], "comment": "32 pages, 1 figure", "categories": [ "math.PR" ], "abstract": "We study a branching Brownian motion $Z$ in $\\mathbb{R}^d$, among obstacles scattered according to a Poisson random measure with a radially decaying intensity. Obstacles are balls with constant radius and each one works as a trap for the whole motion when hit by a particle. Considering a general offspring distribution, we derive the decay rate of the annealed probability that none of the particles of $Z$ hits a trap, asymptotically in time $t$. This proves to be a rich problem motivating the proof of a more general result about the speed of branching Brownian motion conditioned on non-extinction. We provide an appropriate skeleton decomposition for the underlying Galton-Watson process when supercritical and show through a non-trivial comparison that the doomed particles do not contribute to the asymptotic decay rate.", "revisions": [ { "version": "v1", "updated": "2015-07-05T21:35:59.000Z" } ], "analyses": { "subjects": [ "60J80", "60K37", "60F10" ], "keywords": [ "branching brownian motion", "random obstacles", "application", "conditional", "asymptotic decay rate" ], "note": { "typesetting": "TeX", "pages": 32, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv150701277O" } } }