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arXiv · 0909.5167

Scalar field perturbations in Horava-Lifshitz cosmology

Anzhong Wang·David Wands·Roy Maartens
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Abstract

We study perturbations of a scalar field cosmology in Horava-Lifshitz gravity, adopting the most general setup without detailed balance but with the projectability condition. We derive the generalized Klein-Gordon equation, which is sixth-order in spatial derivatives. Then we investigate scalar field perturbations coupled to gravity in a flat Friedmann-Robertson-Walker background. In the sub-horizon regime, the metric and scalar field modes have independent oscillations with different frequencies and phases except in particular cases. On super-horizon scales, the perturbations become adiabatic during slow-roll inflation driven by a single field, and the comoving curvature perturbation is constant.

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Anzhong Wang, David Wands, Roy Maartens. 2009-09-28. Scalar field perturbations in Horava-Lifshitz cosmology. https://doi.org/10.1088/1475-7516/2010/03/013

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