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arXiv · 0809.4238

D-Branes in Orientifolds and Orbifolds and Kasparov KK-Theory

H. Garcia-Compean·W. Herrera-Suarez·B. A. Itza-Ortiz·O. Loaiza-Brito
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Abstract

A classification of D-branes in Type IIB Op^- orientifolds and orbifolds in terms of Real and equivariant KK-groups is given. We classify D-branes intersecting orientifold planes from which are recovered some special limits as the spectrum for D-branes on top of Type I Op^- orientifold and the bivariant classification of Type I D-branes. The gauge group and transformation properties of the low energy effective field theory living in the corresponding unstable D-brane system are computed by extensive use of Clifford algebras. Some speculations about the existence of other versions of KK-groups, based on physical insights, are proposed. In the orbifold case, some known results concerning D-branes intersecting orbifolds are reproduced and generalized. Finally, the gauge theory of unstable systems in these orbifolds is recovered.

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H. Garcia-Compean, W. Herrera-Suarez, B. A. Itza-Ortiz, O. Loaiza-Brito. 2008-09-24. D-Branes in Orientifolds and Orbifolds and Kasparov KK-Theory. https://doi.org/10.1088/1126-6708%2F2008%2F12%2F007

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