{ "id": "0907.5180", "version": "v5", "published": "2009-07-29T17:18:03.000Z", "updated": "2023-04-17T23:13:37.000Z", "title": "Brunet-Derrida particle systems, free boundary problems and Wiener-Hopf equations", "authors": [ "Rick Durrett", "Daniel Remenik" ], "comment": "A mistake in one of the proofs was pointed out to us, but the gap in the argument has been addressed in a recent paper, see Remarks 1.1 and 2.10", "journal": "Annals of Probability 2011, Vol. 39, No. 6, 2043-2078", "doi": "10.1214/10-AOP601", "categories": [ "math.PR" ], "abstract": "We consider a branching-selection system in $\\mathbb {R}$ with $N$ particles which give birth independently at rate 1 and where after each birth the leftmost particle is erased, keeping the number of particles constant. We show that, as $N\\to\\infty$, the empirical measure process associated to the system converges in distribution to a deterministic measure-valued process whose densities solve a free boundary integro-differential equation. We also show that this equation has a unique traveling wave solution traveling at speed $c$ or no such solution depending on whether $c\\geq a$ or $c