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arXiv · hep-th/0103183

Orientifolds, RR Torsion, and K-theory

O. Bergman·E. Gimon·S. Sugimoto
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Abstract

We analyze the role of RR fluxes in orientifold backgrounds from the point of view of K-theory, and demonstrate some physical implications of describing these fluxes in K-theory rather than cohomology. In particular, we show that certain fractional shifts in RR charge quantization due to discrete RR fluxes are naturally explained in K-theory. We also show that some orientifold backgrounds, which are considered distinct in the cohomology classification, become equivalent in the K-theory description, while others become unphysical.

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O. Bergman, E. Gimon, S. Sugimoto. 2001-04-02. Orientifolds, RR Torsion, and K-theory. https://doi.org/10.1088/1126-6708%2F2001%2F05%2F047

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