Massless propagators: applications in QCD and QED

نویسندگان

  • P. A. Baikov
  • K. G. Chetyrkin
  • J. H. Kühn
چکیده

We report on two recent results based on the evaluation of five-loop massless propagators in QCD and QED: (i) corrections of order α 4 s to the absorptive part of the polarization function in QCD with n f = 3; (ii) the five-loop contribution to the β function of quenched QED.

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تاریخ انتشار 2007