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arXiv · 0905.0255

Dynamical Scalar Degree of Freedom in Horava-Lifshitz Gravity

Rong-Gen Cai·Bin Hu·Hong-Bo Zhang
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Abstract

We investigate the linear cosmological perturbations of Hořava-Lifshitz gravity in a FRW universe without any matter. Our results show that a new gauge invariant dynamical scalar mode emerges, due to the gauge transformation under the "foliation-preserving" diffeomorphism and "projectability condition", and it can produce a scale invariant power spectrum. In the infrared regime with $λ=1$, the dynamical scalar degree of freedom turns to be a non-dynamical one at the linear order level.

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Rong-Gen Cai, Bin Hu, Hong-Bo Zhang. 2009-07-28. Dynamical Scalar Degree of Freedom in Horava-Lifshitz Gravity. https://doi.org/10.1103/physrevd.80.041501

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