On the evolution of density perturbations in f(R) theories of gravity
| dc.creator | de la Cruz-Dombriz, A. | |
| dc.creator | Dobado, A. | |
| dc.creator | Maroto, A. L. | |
| dc.date | 2008-02-21 | |
| dc.date | 2008-06-05 | |
| dc.date.accessioned | 2026-07-07T11:56:14Z | |
| dc.date.available | 2026-07-07T11:56:14Z | |
| dc.description | In the context of $f(R)$ theories of gravity, we study the evolution of scalar cosmological perturbations in the metric formalism. Using a completely general procedure, we find the exact fourth-order differential equation for the matter density perturbations in the longitudinal gauge. In the case of sub-Hubble modes, the expression reduces to a second-order equation which is compared with the standard (quasi-static) equation used in the literature. We show that for general $f(R)$ functions the quasi-static approximation is not justified. However, for those functions adequately describing the present phase of accelerated expansion and satisfying local gravity tests, it provides a correct description for the evolution of perturbations. | |
| dc.description | 9 pages, 4 figures. New comments and references included. Final version to appear in Phys.Rev. D | |
| dc.identifier | https://arxiv.org/abs/0802.2999 | |
| dc.identifier | http://arxiv.org/abs/0802.2999 | |
| dc.identifier | Phys.Rev.D77:123515,2008 | |
| dc.identifier | doi:10.1103/PhysRevD.77.123515 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/205512 | |
| dc.subject | Astrophysics | |
| dc.title | On the evolution of density perturbations in f(R) theories of gravity | |
| dc.type | text |