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arXiv · 0803.0303

Mixing internal and spacetime transformations: some examples and counterexamples

R. Percacci
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Abstract

This note addresses the question whether in a gauge theory coupled to gravity internal and spacetime transformation can be mixed. It is shown that if the VEV of the gauge field is flat, the symmetry group is always a product of internal and spacetime symmetries. On the other hand, if the VEV of the gauge field is not flat it is impossible to properly define the notion of a ``spacetime'' transformation; as a consequence, if the symmetry group is nontrivial, mixing generically occurs.

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R. Percacci. 2008-03-03. Mixing internal and spacetime transformations: some examples and counterexamples. https://doi.org/10.1088/1751-8113%2F41%2F33%2F335403

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