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arXiv · hep-th/9807116

A Note on Wess-Zumino Terms and Discrete Symmetries

Silas R. Beane
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Abstract

Sigma models in which the integer coefficient of the Wess-Zumino term vanishes are easy to construct. This is the case if all flavor symmetries are vectorlike. We show that there is a subset of SU(N)XSU(N) vectorlike sigma models in which the Wess-Zumino term vanishes for reasons of symmetry as well. However, there is no chiral sigma model in which the Wess-Zumino term vanishes for reasons of symmetry. This can be understood in the sigma model basis as a consequence of an index theorem for the axialvector coupling matrix. We prove this index theorem directly from the SU(N)XSU(N) algebra.

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Silas R. Beane. 1998-10-22. A Note on Wess-Zumino Terms and Discrete Symmetries. https://doi.org/10.1016/s0370-2693(98)01367-7

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