English

Massive graviton propagation of the deformed Ho\v{r}ava-Lifshitz gravity without projectability condition

High Energy Physics - Theory 2014-11-20 v2 General Relativity and Quantum Cosmology

Abstract

We study graviton propagations of scalar, vector, and tensor modes in the deformed Ho\v{r}ava-Lifshitz gravity (λR\lambda R-model) without projectability condition. The quadratic Lagrangian is invariant under diffeomorphism only for λ=1\lambda=1 case, which contradicts to the fact that λ\lambda is irrelevant to a consistent Hamiltonian approach to the λR\lambda R model. In this case, as far as scalar propagations are concerned, there is no essential difference between deformed Ho\v{r}ava-Lifshitz gravity (λR\lambda R-model) and general relativity. This implies that there are two degrees of freedom for a massless graviton without Ho\v{r}ava scalar, and five degrees of freedom appear for a massive graviton when introducing Lorentz-violating and Fierz-Pauli mass terms. Finally, it is shown that for λ=1\lambda=1, the vDVZ discontinuity is absent in the massless limit of Lorentz-violating mass terms by considering external source terms.

Keywords

Cite

@article{arxiv.1004.2552,
  title  = {Massive graviton propagation of the deformed Ho\v{r}ava-Lifshitz gravity without projectability condition},
  author = {Yun Soo Myung},
  journal= {arXiv preprint arXiv:1004.2552},
  year   = {2014}
}

Comments

21 pages, no figure, version to appear in PLB