Parametrization for the Scale Dependent Growth in Modified Gravity

Autor:	Sanchez, Juan C. Bueno, Dent, James B., Dutta, Sourish, Perivolaropoulos, Leandros
Rok vydání:	2010
Předmět:	Astrophysics - Cosmology and Extragalactic Astrophysics General Relativity and Quantum Cosmology High Energy Physics - Phenomenology High Energy Physics - Theory
Zdroj:	JCAP 1009:021,2010
Druh dokumentu:	Working Paper
DOI:	10.1088/1475-7516/2010/09/021
Popis:	We propose a scale dependent analytic approximation to the exact linear growth of density perturbations in Scalar-Tensor (ST) cosmologies. In particular, we show that on large subhorizon scales, in the Newtonian gauge, the usual scale independent subhorizon growth equation does not describe the growth of perturbations accurately, as a result of scale-dependent relativistic corrections to the Poisson equation. A comparison with exact linear numerical analysis indicates that our approximation is a significant improvement over the standard subhorizon scale independent result on large subhorizon scales. A comparison with the corresponding results in the Synchronous gauge demonstrates the validity and consistency of our analysis. Comment: 10 pages, 5 figures. Minor modifications and references added to match published version
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/1004.4905 Zobrazit plný text záznamu View this record from Arxiv