{ "id": "1302.5012", "version": "v2", "published": "2013-02-20T16:13:35.000Z", "updated": "2017-04-10T15:53:12.000Z", "title": "Coulomb scattering in the massless Nelson model II. Regularity of ground states", "authors": [ "Wojciech Dybalski", "Alessandro Pizzo" ], "comment": "88 pages. Problematic intermediate estimate (5.1) of version 1 eliminated. Main results maintained. Analysis of wave functions shifted to part III of this series of papers", "categories": [ "math-ph", "math.MP" ], "abstract": "For the massless Nelson model we provide detailed information about the dependence of the normalized ground states $\\check{\\psi}_{P,\\sigma}$ of the fiber single-electron Hamiltonians $H_{P,\\sigma}$ on the total momentum $P$ and the infrared cut-off $\\sigma$. This information is obtained with the help of the iterative analytic perturbation theory. In particular, we derive bounds of the form \\[ \\|\\partial_{P_i}\\check{\\psi}_{P,\\sigma}\\|,\\ \\| \\partial_{P_i} \\partial_{P_j}\\check{\\psi}_{P,\\sigma} \\|\\leq \\frac{c}{\\sigma^{\\delta_{\\lambda_0}}}, \\] for some constant $c$ and a function of the maximal admissible coupling constant $\\lambda_0\\mapsto \\delta_{\\lambda_0}$ s.t. $\\lim_{\\lambda_0\\to 0}\\delta_{\\lambda_0}=0$. These results hold both in the infrared-regular and infrared-singular case. They are exploited in part I of this series to construct the two-electron scattering states in the infrared-regular massless Nelson model (in the absence of an infrared cut-off) along the lines of Haag-Ruelle scattering theory. They should also be relevant for the problem of scattering of two infraparticles in the infrared-singular Nelson model, whose solution is the goal of this series of papers. Although a part of a larger investigation, the present work is written in a self-contained fashion.", "revisions": [ { "version": "v1", "updated": "2013-02-20T16:13:35.000Z", "abstract": "For the massless Nelson model we provide detailed information about the dependence of the normalized ground states $\\check{\\psi}_{P,\\sigma}$ of the fiber single-electron Hamiltonians $H_{P,\\sigma}$ on the total momentum $P$ and the infrared cut-off $\\sigma$. This information is obtained with the help of the iterative analytic perturbation theory. In particular, we derive bounds of the form \\[ \\|\\partial_{P}^{\\beta}\\check{\\psi}_{P,\\sigma}\\|\\leq \\frac{c}{\\sigma^{\\delta_{\\lambda_0}}}, \\] for any multiindex $\\beta$, s.t. $0\\leq |\\beta|\\leq 2$ and some function of the maximal admissible coupling constant $\\lambda_0\\mapsto \\delta_{\\lambda_0}$ s.t. $\\lim_{\\lambda_0\\to 0}\\de_{\\lambda_0}=0$. Analogous bounds are obtained for the derivatives w.r.t. $P$ of the $q$-particle momentum wavefunctions $f^q_{P,\\sigma}$ of $\\check{\\psi}_{P,\\sigma}$. These results are exploited in a companion paper to construct the two-electron scattering states in the infrared-regular massless Nelson model (in the absence of an infrared cut-off) along the lines of Haag-Ruelle scattering theory.", "comment": "45 pages", "journal": null, "doi": null }, { "version": "v2", "updated": "2017-04-10T15:53:12.000Z" } ], "analyses": { "keywords": [ "ground states", "coulomb scattering", "regularity", "particle momentum wavefunctions", "infrared cut-off" ], "note": { "typesetting": "TeX", "pages": 88, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2013arXiv1302.5012D" } } }