{ "id": "2405.04335", "version": "v1", "published": "2024-05-07T14:04:32.000Z", "updated": "2024-05-07T14:04:32.000Z", "title": "The tail distribution function of the partition function for directed polymer in the weak disorder phase", "authors": [ "Stefan Junk", "Hubert Lacoin" ], "categories": [ "math.PR" ], "abstract": "We investigate the upper tail distribution of the partition function of the directed polymer in a random environment on $\\mathbb Z^d$ in the weak disorder phase. We show that the distribution of the infinite volume partition function $W^{\\beta}_{\\infty}$ displays a power-law decay, with an exponent $p^*(\\beta)\\in [1+\\frac{2}{d},\\infty)$. We also prove that the distribution of the suprema of the point-to-point and point-to-line partition functions display the same behavior. On the way to these results, we prove a technical estimate of independent interest: the $L^p$-norm of the partition function at the time when it overshoots a high value $A$ is comparable to $A$. We use this estimate to extend the validity of many recent results that were proved under the assumption that the environment is upper bounded.", "revisions": [ { "version": "v1", "updated": "2024-05-07T14:04:32.000Z" } ], "analyses": { "subjects": [ "60K35", "60K37", "82B26", "82B27", "82B44" ], "keywords": [ "weak disorder phase", "tail distribution function", "directed polymer", "infinite volume partition function", "point-to-line partition functions display" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }