{ "id": "2105.03107", "version": "v1", "published": "2021-05-07T08:23:13.000Z", "updated": "2021-05-07T08:23:13.000Z", "title": "New characterization of the weak disorder phase of directed polymers in bounded random environments", "authors": [ "Stefan Junk" ], "categories": [ "math.PR" ], "abstract": "We show that the weak disorder phase for the directed polymer model in a bounded random environment is characterized by the integrability of the running supremum $\\sup_{n\\in \\mathbb N}W_n^\\beta$ of the associated martingale $(W_n^\\beta)_{n\\in \\mathbb N}$. Using this characterization, we prove that $(W_n^\\beta)_{n\\in \\mathbb N}$ is $L^p$-bounded in the whole weak disorder phase, for some $p>1$. The argument generalizes to non-negative martingales with a certain product structure.", "revisions": [ { "version": "v1", "updated": "2021-05-07T08:23:13.000Z" } ], "analyses": { "subjects": [ "60K37" ], "keywords": [ "weak disorder phase", "bounded random environment", "characterization", "directed polymer model", "argument generalizes" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }