{ "id": "quant-ph/0502105", "version": "v1", "published": "2005-02-17T12:55:25.000Z", "updated": "2005-02-17T12:55:25.000Z", "title": "Kepler problem in Dirac theory for a particle with position-dependent mass", "authors": [ "I. O. Vakarchuk" ], "comment": "9 pages", "doi": "10.1088/0305-4470/38/21/016", "categories": [ "quant-ph" ], "abstract": "Exact solution of Dirac equation for a particle whose potential energy and mass are inversely proportional to the distance from the force centre has been found. The bound states exist provided the length scale $a$ which appears in the expression for the mass is smaller than the classical electron radius $e^2/mc^2$. Furthermore, bound states also exist for negative values of $a$ even in the absence of the Coulomb interaction. Quasirelativistic expansion of the energy has been carried out, and a modified expression for the fine structure of energy levels has been obtained. The problem of kinetic energy operator in the Schr\\\"odinger equation is discussed for the case of position-dependent mass. In particular, we have found that for highly excited states the mutual ordering of the inverse mass and momentum operator in the non-relativistic theory is not important.", "revisions": [ { "version": "v1", "updated": "2005-02-17T12:55:25.000Z" } ], "analyses": { "keywords": [ "position-dependent mass", "kepler problem", "dirac theory", "bound states", "kinetic energy operator" ], "tags": [ "journal article" ], "note": { "typesetting": "TeX", "pages": 9, "language": "en", "license": "arXiv", "status": "editable" } } }