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arXiv · hep-th/0112162

Covariant Quantization of Superstrings Without Pure Spinor Constraints

P. A. Grassi·G. Policastro·M. Porrati·P. van Nieuwenhuizen
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Abstract

We construct a covariant quantum superstring, extending Berkovits' approach by introducing new ghosts to relax the pure spinor constraints. The central charge of the underlying Kac-Moody algebra, which would lead to an anomaly in the BRST charge, is treated as a new generator with a new b-c system. We construct a nilpotent BRST current, an anomalous ghost current and an anomaly-free energy-momentum tensor. For open superstrings, we find the correct massless spectrum. In addition, we construct a Lorentz invariant B-field to be used for the computation of the integrated vertex operators and amplitudes.

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P. A. Grassi, G. Policastro, M. Porrati, P. van Nieuwenhuizen. 2001-12-18. Covariant Quantization of Superstrings Without Pure Spinor Constraints. https://doi.org/10.1088/1126-6708%2F2002%2F10%2F054

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