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arXiv · hep-th/9708040

Four-dimensional N=1 Z_N X Z_M Orientifolds

Gysbert Zwart
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Abstract

We calculate the tadpole equations and their solutions for a class of four-dimensional orientifolds with orbifold group Z_N X Z_M, and we present the massless bosonic spectra of these models. Surprisingly we find no consistent solutions for the models with Z_2 X Z_4 and Z_4 X Z_4 orbifold groups.

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Gysbert Zwart. 1998-04-22. Four-dimensional N=1 Z_N X Z_M Orientifolds. https://doi.org/10.1016/s0550-3213(98)00288-0

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