Open Strings and Dualities

Massimo Bianchi

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arXiv · hep-th/9712020

Open Strings and Dualities

Massimo Bianchi

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Abstract

In the fruitful interplay between gauge fields and strings and in many conjectured M-theory dualities, open strings play a prominent role. We review the construction of open-string descendants (un-orientifolds) of closed-string theories admitting a generalized orientation reversal involution. We then specialize the construction to some classes of non-supersymmetric models in D=10 that have been recently considered in the context of duality without supersymmetry. We also discuss the propagation of open and unoriented strings on the NS pentabrane (N5-brane). This background is a prototype of the configurations of branes and orientifold planes that represent a powerful alternative to the geometric engineering of Supersymmetric Yang-Mills Theories. The resulting description of D-branes in non-trivial backgrounds looks very different from the one naively expected. In particular the very distinction between different Dp-branes becomes ambiguous in the presence of strong curvature effects.

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Massimo Bianchi. 1997-12-02. Open Strings and Dualities. https://arxiv.org/abs/hep-th/9712020

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