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arXiv · 1410.5886

Nonperturbative beta function of eight-flavor SU(3) gauge theory

Anna Hasenfratz·David Schaich·Aarti Veernala
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Abstract

We present a new lattice study of the discrete beta function for SU(3) gauge theory with Nf=8 massless flavors of fermions in the fundamental representation. Using the gradient flow running coupling, and comparing two different nHYP-smeared staggered lattice actions, we calculate the 8-flavor step-scaling function at significantly stronger couplings than were previously accessible. Our continuum-extrapolated results for the discrete beta function show no sign of an IR fixed point up to couplings of g^2~14. At the same time, we find that the gradient flow coupling runs much more slowly than predicted by two-loop perturbation theory, reinforcing previous indications that the 8-flavor system possesses nontrivial strongly coupled IR dynamics with relevance to BSM phenomenology.

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Anna Hasenfratz, David Schaich, Aarti Veernala. 2015-06-29. Nonperturbative beta function of eight-flavor SU(3) gauge theory. https://doi.org/10.1007/jhep06(2015)143

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