Analytic perturbation theory in QCD and Schwinger’s connection between the β-function and the spectral density
نویسنده
چکیده
We argue that a technique called analytic perturbation theory leads to a well-defined method for analytically continuing the running coupling constant from the spacelike to the timelike region, which allows us to give a selfconsistent definition of the running coupling constant for timelike momentum. The corresponding β-function is proportional to the spectral density, which confirms a hypothesis due to Schwinger. PACS Numbers: 11.10.Hi, 11.55.Fv, 12.38.Aw, 12.38.Bx Typeset using REVTEX E-mail: [email protected] E-mail: [email protected] 1
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