{ "id": "1402.5864", "version": "v1", "published": "2014-02-24T15:52:16.000Z", "updated": "2014-02-24T15:52:16.000Z", "title": "A necessary and sufficient condition for the non-trivial limit of the derivative martingale in a branching random walk", "authors": [ "Xinxin Chen" ], "categories": [ "math.PR" ], "abstract": "We consider a branching random walk on the line. Biggins and Kyprianou [6] proved that, in the boundary case, the associated derivative martingale converges almost surly to a finite nonnegative limit, whose law serves as a fixed point of a smoothing transformation (Mandelbrot's cascade). In the present paper, we give a necessary and sufficient condition for the non-triviality of this limit and establish a Kesten-Stigum-like result.", "revisions": [ { "version": "v1", "updated": "2014-02-24T15:52:16.000Z" } ], "analyses": { "keywords": [ "branching random walk", "sufficient condition", "non-trivial limit", "boundary case", "associated derivative martingale converges" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014arXiv1402.5864C" } } }