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arXiv · hep-th/9208038

Modular Groups for Twisted Narain Models

J. Erler·M. Spalinski
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Abstract

We demonstrate how to find modular discrete symmetry groups for $Z_N$ orbifolds. The $Z_7$ orbifold is treated in detail as a non-trivial example of a $(2,2)$ orbifold model. We give the generators of the modular group for this case which, surprisingly, does not contain $\sltz^3$ as had been speculated. The treatment models with discrete Wilson lines is also discussed. We consider examples which demonstrate that discrete Wilson lines affect the modular group in a non-trivial manner. In particular, we show that it is possible for a Wilson line to break $SL(2,{\bf Z})$.

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J. Erler, M. Spalinski. 1992-08-13. Modular Groups for Twisted Narain Models. https://doi.org/10.1142/s0217751x94001758

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