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arXiv · 1804.09723

Interactions of multiple spin-2 fields beyond pairwise couplings

S. F. Hassan·Angnis Schmidt-May
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Abstract

Thus far, all known ghost-free interactions of multiple spin-2 fields have involved at most pairwise couplings of the fields, which are direct generalizations of bimetric interactions. Here we present a class of spin-2 theories with genuine multi-field interactions, and explicitly demonstrate the absence of ghost instabilities. The construction involves integrating out a nondynamical field in a theory of spin-2 fields with only pairwise ghost-free interactions. The new multi-vierbein interactions generated are not always expressible in terms of the associated metrics.

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S. F. Hassan, Angnis Schmidt-May. 2018-04-25. Interactions of multiple spin-2 fields beyond pairwise couplings. https://doi.org/10.1103/physrevlett.122.251101

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