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Discrete torsion orbifolds and D-branes II

Ben Craps·Matthias R. Gaberdiel
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Abstract

The consistency of the orbifold action on open strings between D-branes in orbifold theories with and without discrete torsion is analysed carefully. For the example of the C^3/Z_2 x Z_2 theory, it is found that the consistency of the orbifold action requires that the D-brane spectrum contains branes that give rise to a conventional representation of the orbifold group as well as branes for which the representation is projective. It is also shown how the results generalise to the orbifolds C^3/Z_N x Z_N for which a number of novel features arise. In particular, the N>2 theories with minimal discrete torsion have non-BPS branes charged under twisted R-R potentials that couple to none of the (known) BPS branes.

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Ben Craps, Matthias R. Gaberdiel. 2001-04-20. Discrete torsion orbifolds and D-branes II. https://doi.org/10.1088/1126-6708%2F2001%2F04%2F013

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