Topological Charge in Lattice Gauge Theory

Abstract

A useful definition of the topological charge of a lattice gauge-field configuration is given. This definition is used to calculate the topological susceptibility ${\chi }_t=\frac{〈Q^2〉}{V}$ in SU(2) lattice gauge theory by means of a Monte Carlo simulation. ${\chi }_t={(170\mathrm{}\pm 25 \mathrm{MeV})}^4$ is obtained, in good agreement with the current algebra prediction. Other possible uses of this operator are suggested.