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arXiv · hep-th/9604093

Quantisation of 2D-gravity with Weyl and area-preserving diffeomorphism invariances

J. -G. Zhou·Y. -G. Miao·J. -Q. Liang·H. J. W. Mueller-Kirsten·Zhenjiu Zhang
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Abstract

The constraint structure of 2D-gravity with the Weyl and area-preserving diffeomorphism invariances is analysed in the ADM formulation. It is found that when the area-preserving diffeomorphism constraints are kept, the usual conformal gauge does not exist, whereas there is the possibility to choose the so-called ``quasi-light-cone'' gauge, in which besides the area-preserving diffeomorphism invariance, the reduced Lagrangian also possesses the SL(2,R) residual symmetry. The string-like approach is applied to quantise this model, but a fictitious non-zero central charge in the Virasoro algebra appears. When a set of gauge-independent SL(2,R) current-like fields is introduced instead of the string-like variables, a consistent quantum theory is obtained.

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J. -G. Zhou, Y. -G. Miao, J. -Q. Liang, H. J. W. Mueller-Kirsten, Zhenjiu Zhang. 1996-04-17. Quantisation of 2D-gravity with Weyl and area-preserving diffeomorphism invariances. https://arxiv.org/abs/hep-th/9604093

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