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arXiv · 1106.5293

Infrared fixed point of the 12-fermion SU(3) gauge model based on 2-lattice MCRG matching

Anna Hasenfratz
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Abstract

I investigate an SU(3) gauge model with 12 fundamental fermions. The physically interesting region of this strongly coupled system can be influenced by an ultraviolet fixed point due to lattice artifacts. I suggest to use a gauge action with an additional negative adjoint plaquette term that lessens this problem. I also introduce a new analysis method for the 2-lattice matching Monte Carlo renormalization group technique that significantly reduces finite volume effects. The combination of these two improvements allows me to measure the bare step scaling function in a region of the gauge coupling where it is clearly negative, indicating a positive renormalization group $β$ function and infrared conformality.

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Anna Hasenfratz. 2011-06-27. Infrared fixed point of the 12-fermion SU(3) gauge model based on 2-lattice MCRG matching. https://doi.org/10.1103/physrevlett.108.061601

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