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arXiv · 1206.3814

Null Energy Condition violations in bimetric gravity

Valentina Baccetti·Prado Martin-Moruno·Matt Visser
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Abstract

We consider the effective stress-energy tensors for the foreground and background sectors in ghost-free bimetric gravity. By considering the symmetries of the theory, we show that the foreground and background null energy conditions (NECs) are strongly anti-correlated. In particular, the NECs can only be simultaneously fulfilled when they saturate, corresponding to foreground and background cosmological constants. In all other situations, either the foreground or the background is subject to a NEC-violating contribution to the total stress-energy.

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Valentina Baccetti, Prado Martin-Moruno, Matt Visser. 2012-06-27. Null Energy Condition violations in bimetric gravity. https://doi.org/10.1007/jhep08(2012)148

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