{ "id": "1904.08137", "version": "v1", "published": "2019-04-17T08:44:14.000Z", "updated": "2019-04-17T08:44:14.000Z", "title": "A microscopic derivation of Gibbs measures for nonlinear Schrödinger equations with unbounded interaction potentials", "authors": [ "Vedran Sohinger" ], "comment": "77 pages, 5 figures", "categories": [ "math.AP", "math-ph", "math.MP", "math.PR" ], "abstract": "We study the derivation of the Gibbs measure for the nonlinear Schr\\\"{o}dinger equation (NLS) from many-body quantum thermal states in the high-temperature limit. In this paper, we consider the nonlocal NLS with defocusing and unbounded $L^p$ interaction potentials on $\\mathbb{T}^d$ for $d=1,2,3$. This extends the author's earlier joint work with Fr\\\"{o}hlich, Knowles, and Schlein, where the regime of defocusing and bounded interaction potentials was considered. When $d=1$, we give an alternative proof of a result previously obtained by Lewin, Nam, and Rougerie. Our proof is based on a perturbative expansion in the interaction. When $d=1$, the thermal state is the grand canonical ensemble. As in the author's earlier joint work with Fr\\\"{o}hlich, Knowles, and Schlein, when $d=2,3$, the thermal state is a modified grand canonical ensemble, which allows us to estimate the remainder term in the expansion. The terms in the expansion are analysed using a graphical representation and are resummed by using Borel summation. By this method, we are able to prove the result for the optimal range of $p$ and obtain the full range of defocusing interaction potentials which were studied in the classical setting when $d=2,3$ in the work of Bourgain.", "revisions": [ { "version": "v1", "updated": "2019-04-17T08:44:14.000Z" } ], "analyses": { "subjects": [ "35Q55", "60G60", "81V70", "82B10", "35Q40" ], "keywords": [ "nonlinear schrödinger equations", "unbounded interaction potentials", "gibbs measure", "authors earlier joint work", "microscopic derivation" ], "note": { "typesetting": "TeX", "pages": 77, "language": "en", "license": "arXiv", "status": "editable" } } }