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arXiv · hep-th/9909114

Klein Bottles and Simple Currents

L. R. Huiszoon·A. N. Schellekens·N. Sousa
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Abstract

The standard Klein bottle coefficient in the construction of open descendants is shown to equal the Frobenius-Schur indicator of a conformal field theory. Other consistent Klein bottle projections are shown to correspond to simple currents. These observations enable us to generalize the standard open string construction from C-diagonal parent theories to include non-standard Klein bottles. Using (generalizations of) the Frobenius-Schur indicator we prove positivity and integrality of the resulting open and closed string state multiplicities for standard as well as non-standard Klein bottles.

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L. R. Huiszoon, A. N. Schellekens, N. Sousa. 1999-09-20. Klein Bottles and Simple Currents. https://doi.org/10.1016/s0370-2693(99)01241-1

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