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arXiv · 1110.1660

Systematic Errors of the MCRG Method

Simon Catterall·Luigi Del Debbio·Joel Giedt·Liam Keegan
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Abstract

We present a Monte Carlo Renormalisation Group (MCRG) study of the SU(2) gauge theory with two Dirac fermions in the adjoint representation. Using the two-lattice matching technique we measure the running of the coupling and the anomalous mass dimension. We find slow running of the coupling, compatible with an infrared fixed point. Assuming this running is negligible we find a vanishing anomalous dimension, gamma=-0.03(13), however without this assumption our uncertainty in the running of the coupling leads to a much larger range of allowed values, -0.6 < gamma < 0.6. We discuss the systematic errors affecting the current analysis and possible improvements.

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Simon Catterall, Luigi Del Debbio, Joel Giedt, Liam Keegan. 2011-10-07. Systematic Errors of the MCRG Method. https://arxiv.org/abs/1110.1660

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