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arXiv · hep-th/0306014

Twisted Open Strings from Closed Strings: The WZW Orientation Orbifolds

M. B. Halpern·C. Helfgott
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Abstract

Including {\it world-sheet orientation-reversing automorphisms} $\hat{h}_σ \in H_-$ in the orbifold program, we construct the operator algebras and twisted KZ systems of the general WZW {\it orientation orbifold} $A_g (H_-) /H_-$. We find that the orientation-orbifold sectors corresponding to each $\hat{h}_σ \in H_-$ are {\it twisted open} WZW strings, whose properties are quite distinct from conventional open-string orientifold sectors. As simple illustrations, we also discuss the classical (high-level) limit of our construction and free-boson examples on abelian $g$.

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M. B. Halpern, C. Helfgott. 2004-04-02. Twisted Open Strings from Closed Strings: The WZW Orientation Orbifolds. https://doi.org/10.1142/s0217751x04018531

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