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Discrete moduli for Type I compactifications

Arjan Keurentjes
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Abstract

We study type I compactification on a 4-torus, with a non-trivial discrete background RR 4-form field. By using string dualities and recent insights for gauge theories on tori, we find that a non-trivial background for the RR 4-form is correlated with Spin(32)/Z_2 bundles that are described by a ``non-trivial quadruple'' of holonomies. We also briefly discuss other discrete moduli for the type I string, and variants of orientifold planes.

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Arjan Keurentjes. 2001-06-29. Discrete moduli for Type I compactifications. https://doi.org/10.1103/physrevd.65.026007

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