Lattice Studies on 8-Flavor QCD in The Light of Physics Beyond The Standard Model

We report the latest results of the LatKMI collaboration on 8-flavor QCD using Monte Carlo simulations of the lattice gauge theory. The subject receives growing interest with regards to physics beyond the Standard Model (BSM). We show that a flavor-singlet scalar meson (σ) emerges as one of the lightest bound states and can be a composite Higgs boson with mass 125 GeV. The light σ may be a technidilaton, a pseudo Nambu-Goldstone boson of the approximate scale symmetry, which results from a slowly running (walking) coupling constant associated with an infra-red fixed point. Consistently to this reasoning, a mass anomalous dimension γ is found to be large γ∼1. We discuss the applicability of 8-flavor QCD to the BSM model building.