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arXiv · 1912.07624

Gauge coupling beta functions to four-loop order in the Standard Model

Joshua Davies·Florian Herren·Colin Poole·Matthias Steinhauser·Anders Eller Thomsen
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Abstract

We compute the beta functions of the three Standard Model gauge couplings to four-loop order in the modified minimal subtraction scheme. At this order a proper definition of $\gamma_5$ in $D=4-2\epsilon$ space-time dimensions is required; however, in our calculation we determine the $\gamma_5$-dependent terms by exploiting relations with beta function coefficients at lower loop orders.

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Joshua Davies, Florian Herren, Colin Poole, Matthias Steinhauser, Anders Eller Thomsen. 2019-12-16. Gauge coupling beta functions to four-loop order in the Standard Model. https://doi.org/10.1103/physrevlett.124.071803

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