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arXiv · hep-th/9911084

S-duality and Tensionless 5-branes in Compactified Heterotic String Theory

Morten Krogh
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Abstract

We give a simple proof of the known S-duality of Heterotic String theory compactified on a T^6. Using this S-duality we calculate the tensions for a class of BPS 5-branes in Heterotic String theory on a circle. One of these, the Kaluza-Klein monopole, becomes tensionless when the radius of the circle is equal to the string length. We study the question of stability of the Heterotic NS5-brane with a transverse circle. For large radii the NS5-brane is absolutely stable. However for small radii it is only marginally stable. We also study the moduli space of 2 Kaluza-Klein monopoles and show that it is equal to the moduli space of a Heterotic A_1 singularity.

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Morten Krogh. 1999-11-23. S-duality and Tensionless 5-branes in Compactified Heterotic String Theory. https://doi.org/10.1088/1126-6708%2F1999%2F12%2F018

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