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arXiv · hep-th/0602038

D-brane Spectrum and K-theory Constraints of D=4, N=1 Orientifolds

John Maiden·Gary Shiu·Bogdan Stefanski
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Abstract

We study the spectrum of stable BPS and non-BPS D-branes in Z_2 x Z_2 orientifolds for all choices of discrete torsion between the orbifold and orientifold generators. We compute the torsion K-theory charges in these D=4, N=1 orientifold models directly from worldsheet conformal field theory, and compare with the K-theory constraints obtained indirectly using D-brane probes. The K-theory torsion charges derived here provide non-trivial constraints on string model building. We also discuss regions of stability for non-BPS D-branes in these examples.

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John Maiden, Gary Shiu, Bogdan Stefanski. 2006-03-29. D-brane Spectrum and K-theory Constraints of D=4, N=1 Orientifolds. https://doi.org/10.1088/1126-6708%2F2006%2F04%2F052

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