2010/02/28 by Jinn-Ouk Gong, Seoktae Koh, Misao Sasaki · 42 citations
Mathematics · Physics and Astronomy · #Advanced Differential Geometry Research #Black Holes and Theoretical Physics #Classical field theory #Classical mechanics #Cosmology and Gravitation Theories #General relativity #Geometry #Gravitation #Hamiltonian (control theory) #Invariant (physics) #Mathematical physics #Mathematics #Physics #Scalar (mathematics) #Scalar field #Scalar theories of gravitation #Tensor (intrinsic definition) #Theoretical physics #Vector field #astro-ph.CO #gr-qc #hep-th
paper · pdf · doi:10.1103/physrevd.81.084053
published in Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields 81(8) (American Physical Society) · 22 pages; added comments and references, published version
openalex publication_date 2010/04/29 · arxiv created 2010/05/24 · arxiv updated 2010/05/27 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We investigate the linear cosmological perturbations in Ho\ifmmode \checkr\else \vr\fiava-Lifshitz gravity with a scalar field. Starting from the most general expressions of the metric perturbations as well as that of a canonical scalar field, we decompose the scalar, vector, and tensor parts of the perturbed action. By reducing the Hamiltonian, we find that there are two independent degrees of freedom for the tensor perturbations while none for the vector perturbations. For the scalar perturbations, the remaining number of degrees of freedom, which are all gauge invariant, depends on whether the projectable condition is applied or not: two when applied, with one of them being possibly a ghost, and one when not applied. For both cases, we lose the time reparametrization symmetry of any kind.