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arXiv · 0708.0574

Supersymmetry Relations and MHV Amplitudes in Superstring Theory

Stephan Stieberger·Tomasz R. Taylor
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Abstract

We discuss supersymmetric Ward identities relating various scattering amplitudes in type I open superstring theory. We show that at the disk level, the form of such relations remains exactly the same, to all orders in alpha', as in the low-energy effective field theory describing the alpha'-> 0 limit. This result holds in D=4 for all compactifications, even for those that break supersymmetry. We apply SUSY relations to the computations of N-gluon MHV superstring amplitudes, simplifying the existing results for N<7 and deriving a compact expression for N=7.

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Stephan Stieberger, Tomasz R. Taylor. 2007-10-05. Supersymmetry Relations and MHV Amplitudes in Superstring Theory. https://doi.org/10.1016/j.nuclphysb.2007.09.033

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