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Propagators on One-Loop Worldsheets for Orientifolds and Intersecting Branes

F. Epple
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Abstract

We obtain the one-loop propagators in superstring theory for the general case when the worldsheet fields satisfy non-trivial holonomy and/or boundary conditions. Non-trivial holonomy arises in orbifold and orientifold backgrounds whereas non-trivial boundary conditions arise in backgrounds containing D-branes of different dimensionality or D-branes intersecting each other at an angle. In our derivation, we use a generalized version of the method of images. Dihedral groups play a crucial role in constructing the one-loop propagators.

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F. Epple. 2005-01-31. Propagators on One-Loop Worldsheets for Orientifolds and Intersecting Branes. https://doi.org/10.1088/1126-6708%2F2005%2F01%2F043

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