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arXiv · hep-th/0106267

Classifying orientifolds by flat n-gerbes

Arjan Keurentjes
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Abstract

The discrete tensorial charges carried by orientifold planes define n-gerbes in space-time. The simplest way to ensure a consistent string compactification is to require these gerbes to be flat. This results in expressions for the local gerbe-holonomies around each orientifold plane, describing its charges. Inverting the procedure and considering all flat gerbes leads to a classification of orientifold configurations. Requiring that the tadpole is cancelled by adding D-branes, we classify all supersymmetric orientifolds on T^k/Z_2 with 2^k O(9-k) planes at the fixed points, for k less or equal to 6. For k=6 these theories organize in orbits of the SL(2,Z) S-duality symmetry of N=4 supersymmetric gauge theories.

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Arjan Keurentjes. 2001-08-17. Classifying orientifolds by flat n-gerbes. https://doi.org/10.1088/1126-6708%2F2001%2F07%2F010

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