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arXiv · hep-th/0004100

Crosscaps, Boundaries and T-Duality

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

Open descendants with boundaries and crosscaps of non-trivial automorphism type are studied. We focus on the case where the bulk symmetry is broken to a Z_2 orbifold subalgebra. By requiring positivity and integrality for the open sector, we derive a unique crosscap of automorphism type g \in Z_2 and a corresponding g-twisted Klein bottle for a charge conjugation invariant. As a specific example, we use T-duality to construct the descendants of the true diagonal invariant with symmetry preserving crosscaps and boundaries.

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L. R. Huiszoon, A. N. Schellekens. 2000-04-13. Crosscaps, Boundaries and T-Duality. https://doi.org/10.1016/s0550-3213(00)00320-5

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