Semi-Invariant Terms for Gauged Non-Linear Sigma-Models

Abstract

We determine all the terms that are gauge-invariant up to a total spacetime derivative ("semi-invariant terms") for gauged non-linear sigma models. Assuming that the isotropy subgroup $H$ of the gauge group is compact or semi-simple, we show that (non-trivial) such terms exist only in odd dimensions and are equivalent to the familiar Chern-Simons terms for the subgroup $H$. Various applications are mentioned, including one to the gauging of the Wess-Zumino-Witten terms in even spacetime dimensions. Our approach is based on the analysis of the descent equation associated with semi-invariant terms.

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References in corpus (2)

• Local BRST cohomology of the gauged principal non-linear sigma model
• Properties of Gauged Sigma Models

Cited by in corpus (1)

• Local BRST cohomology in gauge theories