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arXiv · hep-th/9912016

Ward identities and the vanishing theorem for loop amplitudes of the closed N=2 string

Klaus Junemann·Olaf Lechtenfeld
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Abstract

The existence of a ground ring of ghost number zero operators in the chiral BRST cohomology of the N=2 string is used to derive an infinite set of Ward identities for the closed-string scattering amplitudes at arbitrary genus. These identities are sufficient to rederive the well known vanishing theorem for loop amplitudes with more than three external legs.

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Klaus Junemann, Olaf Lechtenfeld. 1999-12-02. Ward identities and the vanishing theorem for loop amplitudes of the closed N=2 string. https://doi.org/10.1016/s0370-2693(00)00014-9

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