Investigation of Discrete Gauge Anomalies in String Theory

In string theory, there are no continuous global symmetries. Discrete symmetries frequently appear, and these can often be understood as unbroken subgroups of larger, spontaneously broken gauge symmetries (discrete gauge symmetries). In cases which have been studied previously, anomalies in these symmetries could always be cancelled by a Green-Schwarz mechanism. In the present work, we describe results of an investigation of a large number of $\ZZ_3$ orbifold models with two and three Wilson lines. We find that the discrete gauge anomalies can always be cancelled.}