Line Operators in the Standard Model

Abstract

There is an ambiguity in the gauge group of the Standard Model. The group is $G=SU(3)\times SU(2)\times U(1)/\Gamma$, where $\Gamma$ is a subgroup of ${\mathbf{Z}}_6$ which cannot be determined by current experiments. We describe how the electric, magnetic and dyonic line operators of the theory depend on the choice of $\Gamma$. We also explain how the periodicity of the theta angles, associated to each factor of $G$, differ.

Comments: 17 pages. 5 figures. v2: typos corrected