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arXiv · hep-th/0109197

Novel Type I Compactifications

Abstract

We argue that there are two distinct classes of type I compactification to four dimensions on any space. These two classes are distinguished in a mysterious way by the presence (or absence) of a discrete 6-form potential. In simple examples, duality suggests that the new class of compactifications have reduced numbers of moduli. We also point out analogous discrete choices in M, F and type II compactifications, including some with $G_2$ holonomy. These choices often result in spaces with frozen singularities.

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David R. Morrison, Savdeep Sethi. 2001-11-06. Novel Type I Compactifications. https://doi.org/10.1088/1126-6708%2F2002%2F01%2F032

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