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Practicalities of renormalizing quantum field theories

J. A. Gracey
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Abstract

We review the techniques used to renormalize quantum field theories at several loop orders. This includes the techniques to systematically extract the infinities in a Feynman integral and the implementation of the algorithm within computer algebra. To illustrate the method we discuss the renormalization of phi^4 theory and QCD including the application of the critical point large $N$ technique as a check on the anomalous dimensions. The renormalization of non-local operators in QCD is also discussed including the derivation of the two loop correction to the Gribov mass gap equation in the Landau gauge.

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J. A. Gracey. 2006-05-03. Practicalities of renormalizing quantum field theories. https://arxiv.org/abs/hep-th/0605037

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