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arXiv · hep-th/9409007

BRST Charge for the Orthogonal Series of Bershadsky-Knizhnik Quasi-Superconformal Algebras

Sergei V. Ketov
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Abstract

The quantum BRST charges for the Bershadsky-Knizhnik orthogonal quasi-superconformal algebras are constructed. These two-dimensional superalgebras have the $N$-extended non-linearly realised supersymmetry and the $SO(N)$ internal symmetry. The BRST charge nilpotency conditions are shown to have a unique solution at $N>2$, namely, $N=4$ and $k=-2$, where $k$ is central extension parameter of the Kač-Moody subalgebra. We argue about the existence of a new string theory with the non-linearly realised $N=4$ world-sheet supersymmetry and negative `critical dimension'.

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Sergei V. Ketov. 1994-09-01. BRST Charge for the Orthogonal Series of Bershadsky-Knizhnik Quasi-Superconformal Algebras. https://arxiv.org/abs/hep-th/9409007

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