1212.1353 (Etsuko Itou)

Properties of the twisted Polyakov loop coupling and the infrared fixed
point in the SU(3) gauge theory    [PDF]

Etsuko Itou

We give a summary report for the nonperturbative behaviors of the twisted Polyakov loop (TPL) coupling constant for the SU(3) gauge theory, which is one of the nonperturbative renormalized coupling constants defined in finite volume. We reveal several properties for the lattice gauge theory with the twisted boundary condition and carry out the numerical simulations in the cases of the quenched QCD and N_f=12 SU(3) theories. At first, we study the quenched QCD theory by using the plaquette gauge action. The TPL coupling constant shows a fake fixed point in the Coulomb phase even in the quenched QCD. We discuss this property and show the nonperturbative running coupling constant. We also investigate the system coupled with fundamental fermions. In the simulation, we use the naive staggered fermion and the minimum number of flavor is 12 in this lattice setup because of the twisted boundary condition. The N_f=12 SU(3) gauge theory is expected that the running coupling constant shows the different behavior form the quenched QCD case. We show the vacuum structure of this lattice setup with analytical and numerical methods, and then show the detailed analysis of the running coupling constant of this theory. Finally, we find the infrared fixed point (IRFP) and discuss the robustness of the nontrivial IRFP of many flavor system under the change of the analysis method. A part of preliminary results was reported in the proceedings [1][2] and the letter paper [3], and in this paper we review the results and show the final conclusion for the IRFP of SU(3) N_f=12 massless theory.

View original: http://arxiv.org/abs/1212.1353