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Spacetime Supersymmetry and Duality in String Theory

Ramzi R. Khuri
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Abstract

I discuss the role of spacetime supersymmetry in the interplay between strong/weak coupling duality and target space duality in string theory which arises in string/string duality. This can be seen via the construction of string soliton solutions which in $N=4$ compactifications of heterotic string theory break more than $1/2$ of the spacetime supersymmetries but whose analogs in $N=2$ and $N=1$ compactifications break precisely $1/2$ of the spacetime supersymmetries. As a result, these solutions may be interpreted as stable solitons in the latter two cases, and correspond to Bogomol'nyi-saturated states in their respective spectra.

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Ramzi R. Khuri. 1995-06-13. Spacetime Supersymmetry and Duality in String Theory. https://arxiv.org/abs/hep-th/9506086

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