# Higher-Loop Corrections to the Infrared Evolution of a Gauge Theory with Fermions

Thomas Ryttov, Robert Shrock

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## Abstract

We consider a vectorial, asymptotically free gauge theory and analyze the effect of higher-loop corrections to the beta function on the evolution of the theory from the ultraviolet to the infrared. We study the case in which the theory contains $N_f$ copies of a fermion transforming according to the fundamental representation and several higher-dimensional representations of the gauge group. We also calculate higher-loop values of the anomalous dimension of the mass, $\gamma_m$ of $\bar\psi\psi$ at the infrared zero of the beta function. We find that for a given theory, the values of $\gamma_m$ calculated to three- and four-loop order, and evaluated at the infrared zero computed to the same order, tend to be somewhat smaller than the value calculated to two-loop order. The results are compared with recent lattice simulations.
Translated title of the contribution Higher-Loop Corrections to the Infrared Evolution of a Gauge Theory with Fermions English Phys.Rev.D https://doi.org/10.1103/PhysRevD.83.056011 Published - 20. Nov 2010 Yes

• hep-ph