Numerical results for gauge theories near the conformal window

TL;DR

This paper reviews lattice simulation methods and presents results on SU(2) gauge theory with one adjoint Dirac fermion, indicating near-conformal behavior relevant for models beyond the standard model.

Contribution

It provides the first detailed lattice analysis of SU(2) gauge theory with one adjoint fermion, demonstrating its near-conformal dynamics and estimating the anomalous dimension.

Findings

SU(2) gauge theory with one adjoint fermion exhibits near-conformal behavior

The anomalous dimension is approximately one

Implications for beyond Standard Model physics are discussed

Abstract

A novel strong interaction beyond the standard model could provide a dynamical explanation of electroweak symmetry breaking. Experimental results strongly constrain properties of models that realise this mechanism. Whether these constraints are obeyed by any strongly interacting quantum field theory is a non-perturbative problem that needs to be addressed by first-principle calculations. Monte Carlo simulations of lattice regularised gauge theories is a powerful tool that enables us to address this question. Recently various lattice investigations have appeared that have studied candidate models of strongly interacting dynamics beyond the standard model. After a brief review of the main methods and of some recent results, we focus on the analysis of SU(2) gauge theory with one adjoint Dirac fermion flavour, which is shown to have a near-conformal behaviour with an anomalous dimension of order one. The implications of our findings are also discussed.