Note on stability of de Sitter solutions of f(R) theories
- Departamento de Fisica, Universidad Central de Las Villas, 54830 Santa Clara (Cuba)
- Departamento de Matematica, Universidad Central de Las Villas, 54830 Santa Clara (Cuba)
The consequences of the constraints which stability of de Sitter solutions of f(R) theories imposes on the Lagrangian's parameters are investigated within the metric formalism. It is shown, in particular, that several common f(R) Lagrangians do not actually admit matching of local solutions with background de Sitter spaces. Otherwise, asymptotic matching of local solutions of the corresponding models with maximally symmetric spaces of constant curvature is either unstable or anti-de Sitter space is the only stable asymptotic solution. Additional arguments are given in favor of a previous claim that a class of f(R) models comprising both positive and negative powers of R (two different mass scales) could be a nice scenario in which to address, in a united picture, both early-time inflation and late-time accelerated expansion of the Universe. The approach undertaken here is used, also, to check ghost freedom of a Dirac-Born-Infeld modification of general relativity previously studied in the literature.
- OSTI ID:
- 21316245
- Journal Information:
- Physical Review. D, Particles Fields, Vol. 80, Issue 2; Other Information: DOI: 10.1103/PhysRevD.80.024022; (c) 2009 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
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