Twisted reduction in large N QCD with two adjoint Wilson fermions

TL;DR

This paper investigates the twisted reduced model of large N QCD with two adjoint Wilson fermions, revealing potential conformal behavior and an infrared fixed point through numerical simulations of string tension and mass dependencies.

Contribution

It provides the first numerical analysis of the twisted reduced model with non-zero flux, showing significant differences from periodic boundary conditions and suggesting conformal dynamics.

Findings

String tension vanishes as quark mass approaches zero

Model exhibits behavior consistent with an infrared fixed point

Differences observed between twisted and periodic boundary conditions

Abstract

The twisted reduced model of large $N$ QCD with two adjoint Wilson fermions is studied numerically using the Hybrid Monte Carlo method. This is the one-site model, whose large $N$ limit (large volume limit) is expected to be conformal or nearly conformal. The symmetric twist boundary condition with flux $k$ is used. $k$=0 corresponds to periodic boundary conditions. It is shown that the quark mass and $N$ dependencies of the model with non-vanishing $k$ differ significantly from those of the $k$=0 model. A preliminary result for the string tension calculated at $N$=289 is presented. The string tension seems to vanish as the physical quark mass decreases to zero in a way consistent with the theory being governed by an infrared fixed point with $\gamma_* = 0.8 \sim 1.2$.