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arXiv · 1104.2534

Consistency of Relevant Cosmological Deformations on all Scales

Felix Berkhahn·Dennis D. Dietrich·Stefan Hofmann
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Abstract

Using cosmological perturbation theory we show that the most relevant defor- mation of gravity is consistent at the linear level. In particular, we prove the absence of uni- tarity violating negative norm states in the weak coupling regime from sub- to super-Hubble scales. This demonstrates that the recently proposed classical self-protection mechanism of deformed gravity extends to the entire kinematical domain.

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Felix Berkhahn, Dennis D. Dietrich, Stefan Hofmann. 2011-04-13. Consistency of Relevant Cosmological Deformations on all Scales. https://doi.org/10.1088/1475-7516/2011/09/024

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