Stable, Accelerating Universes in Modified Gravity
| dc.creator | DeDeo, Simon | |
| dc.creator | Psaltis, Dimitrios | |
| dc.date | 2007-12-23 | |
| dc.date | 2008-11-13 | |
| dc.date.accessioned | 2026-07-07T12:43:43Z | |
| dc.date.available | 2026-07-07T12:43:43Z | |
| dc.description | Modifications to gravity that add additional functions of the Ricci curvature to the Einstein-Hilbert action -- collectively known as $f(R)$ theories -- have been studied in great detail. When considered as complete theories of gravity they can generate non-perturbative deviations from the general relativistic predictions in the solar system, and the simplest models show instabilites on cosmological scales. Here we show that it is possible to treat $f(R)=R\pmμ^4/R$ gravity in a perturbative fashion such that it shows no instabilities on cosmological scales and, in the solar system, is consistent with measurements of the PPN parameters. We show that such a theory produces a spatially flat, accelerating universe, even in the absence of dark energy and when the matter density is too small to close the universe in the general relativistic case. | |
| dc.description | 5 pages, 1 figure, matches published version | |
| dc.identifier | https://arxiv.org/abs/0712.3939 | |
| dc.identifier | http://arxiv.org/abs/0712.3939 | |
| dc.identifier | Phys.Rev.D78:064013,2008 | |
| dc.identifier | doi:10.1103/PhysRevD.78.064013 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/220520 | |
| dc.subject | Astrophysics | |
| dc.title | Stable, Accelerating Universes in Modified Gravity | |
| dc.type | text |