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arXiv · hep-th/9404170

Canonical BRST Quantisation of Worldsheet Gravities

R. Mohayaee·C. N. Pope·K. S. Stelle·K. W. Xu
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Abstract

We reformulate the BRST quantisation of chiral Virasoro and $W_3$ worldsheet gravities. Our approach follows directly the classic BRST formulation of Yang-Mills theory in employing a derivative gauge condition instead of the conventional conformal gauge condition, supplemented by an introduction of momenta in order to put the ghost action back into first-order form. The consequence of these simple changes is a considerable simplification of the BRST formulation, the evaluation of anomalies and the expression of Wess-Zumino consistency conditions. In particular, the transformation rules of all fields now constitute a canonical transformation generated by the BRST operator $Q$, and we obtain in this reformulation a new result that the anomaly in the BRST Ward identity is obtained by application of the anomalous operator $Q^2$, calculated using operator products, to the gauge fermion.

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R. Mohayaee, C. N. Pope, K. S. Stelle, K. W. Xu. 1994-04-30. Canonical BRST Quantisation of Worldsheet Gravities. https://doi.org/10.1016/0550-3213(94)00404-3

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