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arXiv · hep-th/9307071

The Algebra of Non-Local Charges in Non-Linear Sigma Models

E. Abdalla·M. C. B. Abdalla·J. C. Brunelli·A. Zadra
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Abstract

We obtain the exact Dirac algebra obeyed by the conserved non-local charges in bosonic non-linear sigma models. Part of the computation is specialized for a symmetry group $O(N)$. As it turns out the algebra corresponds to a cubic deformation of the Kac-Moody algebra. The non-linear terms are computed in closed form. In each Dirac bracket we only find highest order terms (as explained in the paper), defining a saturated algebra. We generalize the results for the presence of a Wess-Zumino term. The algebra is very similar to the previous one, containing now a calculable correction of order one unit lower.

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E. Abdalla, M. C. B. Abdalla, J. C. Brunelli, A. Zadra. 1993-07-09. The Algebra of Non-Local Charges in Non-Linear Sigma Models. https://doi.org/10.1007/bf02112321

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