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

TL;DR

This paper studies an SU(3) gauge model with 12 fermions, using improved lattice techniques to identify an infrared fixed point indicating conformal behavior, which is relevant for understanding strong coupling dynamics.

Contribution

It introduces a negative adjoint plaquette term in the gauge action and a new 2-lattice matching method to reduce finite volume effects, enabling clearer detection of the IR fixed point.

Findings

Identification of a negative bare step scaling function

Evidence for an infrared conformal fixed point

Reduction of finite volume effects in the analysis

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 $\beta$ function and infrared conformality.