2014/06/05 by J. B. Kogut, D. K. Sinclair
Physics and Astronomy · #Coupling (piping) #Coupling constant #Diffraction #Gauge theory #High-Energy Particle Collisions Research #Lattice (music) #Lattice QCD #Lattice constant #Lattice field theory #Lattice gauge theory #Materials science #Mathematical physics #Particle physics #Particle physics theoretical and experimental studies #Physics #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #Quantum mechanics #Quark #hep-lat
paper · pdf · doi:10.1103/physrevd.90.014506
published as Phys. Rev. D 90, 014506 (2014) · 17 pages, 6 figures, LaTeX with postscript figures
arxiv created 2014/06/05 · openalex publication_date 2014/07/15 · arxiv updated 2014/07/23 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We have been studying QCD with two flavors of color-sextet quarks as a candidate walking-technicolor theory using lattice-QCD simulations. The evolution of the coupling constant with lattice spacing is measured at the finite-temperature chiral transition to determine if this theory is asymptotically free and hence QCD-like. The lattice spacing is varied by changing the number of lattice sites, Nt, in the Euclidean time direction. QCD with three flavors is studied for comparison. Since this theory is expected to be conformal, with an infrared fixed point, the coupling constant at the chiral transition should approach a nonzero value as Nt becomes large. Our earlier simulations on lattices with Nt=4 and Nt=6 exhibited a significant decrease in coupling at the chiral transition as Nt was increased. We have now extended these simulations to Nt=8, and performed additional simulations at Nt=6 to measure the coupling constant at the chiral transition more precisely. These indicate that while there is an appreciable decrease in coupling between Nt=6 and Nt=8, this is much smaller than that between Nt=4 and Nt=6. Thus we are hopeful that we are approaching the large-Nt limit. However, further simulations at larger Nt(s) are needed.