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arXiv · hep-th/0701049

Gauge Symmetry and Consistent Spin-Two Theories

D. Blas
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Abstract

We study Lagrangians with the minimal amount of gauge symmetry required to propagate spin-two particles without ghosts or tachyons. In general, these Lagrangians also have a scalar mode in their spectrum. We find that, in two cases, the symmetry can be enhanced to a larger group: the whole group of diffeomorphisms or a enhancement involving a Weyl symmetry. We consider the non-linear completions of these theories. The intuitive completions yield the usual scalar-tensor theories except for the pure spin-two cases, which correspond to two inequivalent Lagrangians giving rise to Einstein's equations. A more constructive self-consistent approach yields a background dependent Lagrangian.

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D. Blas. 2007-01-12. Gauge Symmetry and Consistent Spin-Two Theories. https://doi.org/10.1088/1751-8113%2F40%2F25%2Fs47

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