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arXiv · hep-th/9310112

A WZW model based on a non-semi-simple group

C. R. Nappi·E. Witten
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Abstract

We present a conformal field theory which desribes a homogeneous four dimensional Lorentz-signature space-time. The model is an ungauged WZW model based on a central extension of the Poincaré algebra. The central charge of this theory is exactly four, just like four dimensional Minkowski space. The model can be interpreted as a four dimensional monochromatic plane wave. As there are three commuting isometries, other interesting geometries are expected to emerge via $O(3,3)$ duality.

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C. R. Nappi, E. Witten. 1993-10-19. A WZW model based on a non-semi-simple group. https://doi.org/10.1103/physrevlett.71.3751

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