English

Scalar field perturbations in Horava-Lifshitz cosmology

High Energy Physics - Theory 2010-04-27 v3 Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology High Energy Physics - Phenomenology

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.

Keywords

Cite

@article{arxiv.0909.5167,
  title  = {Scalar field perturbations in Horava-Lifshitz cosmology},
  author = {Anzhong Wang and David Wands and Roy Maartens},
  journal= {arXiv preprint arXiv:0909.5167},
  year   = {2010}
}

Comments

Revtex4, no figures. Version published in JCAP 03, 013 (2010).