English

Dynamical Scalar Degree of Freedom in Horava-Lifshitz Gravity

High Energy Physics - Theory 2009-09-02 v3 Cosmology and Nongalactic Astrophysics General Relativity and Quantum Cosmology

Abstract

We investigate the linear cosmological perturbations of Ho\v{r}ava-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\lambda=1, the dynamical scalar degree of freedom turns to be a non-dynamical one at the linear order level.

Keywords

Cite

@article{arxiv.0905.0255,
  title  = {Dynamical Scalar Degree of Freedom in Horava-Lifshitz Gravity},
  author = {Rong-Gen Cai and Bin Hu and Hong-Bo Zhang},
  journal= {arXiv preprint arXiv:0905.0255},
  year   = {2009}
}

Comments

5pages, no figures, references added, version to appear in PRD(R)