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arXiv · hep-th/9901164

Non-local symmetries of the closed N=2 string

Klaus Junemann·Olaf Lechtenfeld·Alexander D. Popov
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Abstract

By carefully analysing the picture-dependence of the BRST cohomology an infinite set of symmetry charges of the closed N=2 string is identified. The transformation laws of the physical vertex operators are shown to coincide with the linearised non-local symmetries of the Plebanski equation (which is the effective field theory of the closed N=2 string). Moreover, the corresponding Ward identities are powerful enough to allow for a rederivation of the well known vanishing theorem for the tree-level correlation functions with more than three external legs.

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Klaus Junemann, Olaf Lechtenfeld, Alexander D. Popov. 1999-01-29. Non-local symmetries of the closed N=2 string. https://doi.org/10.1016/s0550-3213(99)00156-x

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