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arXiv · hep-th/9607057

Orbifold and Orientifold Compactifications of F-Theory and M-Theory to Six and Four Dimensions

Rajesh Gopakumar·Sunil Mukhi
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Abstract

We study orbifold compactifications of F-theory which lead to $N=1$ supersymmetry in 6 and 4 spacetime dimensions. These are dual to specific orientifolds of M-theory, and in many cases to orientifolds of type IIB string theory. The equivalences are demonstrated by mapping the orbifolding transformations in the F, M and string theories to each other using dualities. We observe that M and F-theory appear to possess a property similar to discrete torsion in string theory. This is related to an ambiguity recently noted by Polchinski in the orientifold projection for 6-dimensional models. The 4-dimensional compactifications exhibit similar features, from which we predict the existence of certain new orientifolds of type IIB. Some orbifolds with higher supersymmetry are also examined.

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Rajesh Gopakumar, Sunil Mukhi. 1996-07-22. Orbifold and Orientifold Compactifications of F-Theory and M-Theory to Six and Four Dimensions. https://doi.org/10.1016/0550-3213(96)00460-9

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