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arXiv · hep-th/9307027

The WZNW Model at Two Loops

B. de Wit·M. T. Grisaru·P. van Nieuwenhuizen
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Abstract

We study perturbatively the (conformal) WZNW model. At one loop we compute one-particle irreducible two- and three-point current correlation functions, both in the conventional version and in the classically equivalent, chiral, nonlocal, induced version of the model. At two loops we compute the two-point function and find that it vanishes (modulo infrared-induced logarithms). We use dimensional regularization and the $R^*$ operation for removing infrared divergences. The outcome of the calculations is insensitive to the treatment of the $\varepsilon^{\m\n}$ tensor as a two-dimensional or $d$-dimensional object. Our results indicate that the one-particle irreducible current correlation functions constitute an effective action equal to the original WZNW action with the familiar level shift, $k\to k+\tilde h$.

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B. de Wit, M. T. Grisaru, P. van Nieuwenhuizen. 1993-07-05. The WZNW Model at Two Loops. https://doi.org/10.1016/0550-3213(93)90537-y

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