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arXiv · 1109.3515

Bimetric Gravity from Ghost-free Massive Gravity

S. F. Hassan·Rachel A. Rosen
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Abstract

Generically, non-linear bimetric theories of gravity suffer from the same Boulware-Deser ghost instability as non-linear theories of massive gravity. However, recently proposed theories of massive gravity have been shown to be ghost-free. These theories are formulated with respect to a flat, non-dynamical reference metric. In this work we show that it is possible to give dynamics to the reference metric in such a way that the consistency of the theory is maintained. The result is a non-linear bimetric theory of a massless spin-2 field interacting with a massive spin-2 field that is free of the Boulware-Deser ghost. To our knowledge, this is the first construction of such a ghost-free bimetric theory.

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S. F. Hassan, Rachel A. Rosen. 2012-04-03. Bimetric Gravity from Ghost-free Massive Gravity. https://doi.org/10.1007/jhep02(2012)126

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