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arXiv · hep-th/9712182

Chiral BRST Cohomology of N=2 Strings at Arbitrary Ghost and Picture Number

Klaus Junemann·Olaf Lechtenfeld
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Abstract

We compute the BRST cohomology of the holomorphic part of the N=2 string at arbitrary ghost and picture number. We confirm the expectation that the relative cohomology at non-zero momentum consists of a single massless state in each picture. The absolute cohomology is obtained by an independent method based on homological algebra. For vanishing momentum, the relative and absolute cohomologies both display a picture dependence -- a phenomenon discovered recently also in the relative Ramond sector of N=1 strings by Berkovits and Zwiebach.

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Klaus Junemann, Olaf Lechtenfeld. 1997-12-18. Chiral BRST Cohomology of N=2 Strings at Arbitrary Ghost and Picture Number. https://doi.org/10.1007/s002200050605

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