{ "id": "1506.08079", "version": "v1", "published": "2015-06-26T13:57:13.000Z", "updated": "2015-06-26T13:57:13.000Z", "title": "Time delay for the Dirac equation", "authors": [ "Ivan Naumkin", "Ricardo Weder" ], "categories": [ "math-ph", "math.MP", "quant-ph" ], "abstract": "We consider time delay for the Dirac equation. A new method to calculate the asymptotics of the expectation values of the operator $\\int\\limits_{0} ^{\\infty}e^{iH_{0}t}\\zeta\\left( \\frac{\\left\\vert x\\right\\vert }{R}\\right) e^{-iH_{0}t}dt,$ as $R\\rightarrow\\infty,$ is presented. Here $H_{0}$ is the free Dirac operator and $\\zeta\\left( t\\right) $ is such that $\\zeta\\left( t\\right) =1$ for $0\\leq t\\leq1$ and $\\zeta\\left( t\\right) =0$ for $t>1.$ This approach allows us to obtain the time delay operator $\\delta \\mathcal{T}\\left( f\\right) $ for initial states $f$ in $\\mathcal{H} _{2}^{3/2+\\varepsilon}\\left( \\mathbb{R}^{3};\\mathbb{C}^{4}\\right) ,$ $\\varepsilon>0,$ the Sobolev space of order $3/2+\\varepsilon$ and weight $2.$ The relation between the time delay operator $\\delta\\mathcal{T}\\left( f\\right) $ and the Eisenbud-Wigner time delay operator is given. Also, the relation between the averaged time delay and the spectral shift function is presented.", "revisions": [ { "version": "v1", "updated": "2015-06-26T13:57:13.000Z" } ], "analyses": { "subjects": [ "35Q40", "35P25", "35Q41", "81U99" ], "keywords": [ "dirac equation", "eisenbud-wigner time delay operator", "spectral shift function", "free dirac operator", "expectation values" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2015arXiv150608079N" } } }