Abstract
We analyze the stability of the Einstein static universe by considering homogeneous scalar perturbations in the context of modified theories of gravity. By considering specific forms of , the stability regions of the solutions are parametrized by a linear equation of state parameter . Contrary to classical general relativity, it is found that in gravity a stable Einstein cosmos with a positive cosmological constant does indeed exist. Thus, we are lead to conclude that, in principle, modifications in gravity stabilize solutions which are unstable in general relativity.
- Received 18 June 2007
DOI:https://doi.org/10.1103/PhysRevD.76.084005
©2007 American Physical Society