Asymptotic Padé Approximant Predictions: up to Five Loops in QCD and SQCD

نویسنده

  • J. Ellis
چکیده

We use Asymptotic Padé Approximants (APAP’s) to predict the fourand five-loop β functions in QCD and N = 1 supersymmetric QCD (SQCD), as well as the quark mass anomalous dimensions in Abelian and non-Abelian gauge theories. We show how the accuracy of our previous β-function predictions at the four-loop level may be further improved by using estimators weighted over negative numbers of flavours (WAPAP’s). The accuracy of the improved four-loop results encourages confidence in the new five-loop β-function predictions that we present. However, the WAPAP approach does not provide improved results for the anomalous mass dimension, or for Abelian theories.

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تاریخ انتشار 1997