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arXiv · hep-th/9504160

Gauging of Nonlinearly Realized Symmetries

I. N. McArthur
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Abstract

A representation of a subgroup H of a finite-dimensional group G can be used to induce a nonlinear realization of G. If the nonlinearly realized symmetry is gauged, then the BRST charge can be related by a similarity transformation to the BRST charge for the gauged linear realization of H (plus a cohomologically trivial piece). It is shown that the relation between the two BRST charges is a reflection of the fact that they can be interpreted geometrically as expressions for the exterior derivative on G relative to two different bases, and an explicit expression for the generator of the similarity transformation is obtained. This result is applied in an infinite-dimensional setting, where it yields the similarity transformation used by Ishikawa and Kato to prove the equivalence of the Berkovits-Vafa superstring with the underlying bosonic string theory.

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I. N. McArthur. 1995-04-29. Gauging of Nonlinearly Realized Symmetries. https://doi.org/10.1016/0550-3213(95)00288-4

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