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arXiv · hep-th/0003024

Asymmetric Orbifolds, Noncommutative Geometry and Type I String Vacua

Ralph Blumenhagen·Lars Goerlich·Boris Kors·Dieter Lust
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Abstract

We investigate the D-brane contents of asymmetric orbifolds. Using T-duality we find that the consistent description of open strings in asymmetric orbifolds requires to turn on background gauge fields on the D-branes. We derive the corresponding noncommutative geometry arising on such D-branes with mixed Neumann-Dirichlet boundary conditions directly by applying an asymmetric rotation to open strings with pure Dirichlet or Neumann boundary conditions. As a concrete application of our results we construct asymmetric type I vacua requiring open strings with mixed boundary conditions for tadpole cancellation.

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Ralph Blumenhagen, Lars Goerlich, Boris Kors, Dieter Lust. 2000-03-14. Asymmetric Orbifolds, Noncommutative Geometry and Type I String Vacua. https://doi.org/10.1016/s0550-3213(00)00270-4

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