Higher powers in gravitation

Journal Article · Wed Oct 15 04:00:00 EDT 2008 · Physical Review. D, Particles Fields

DOI:https://doi.org/10.1103/PHYSREVD.78.083501· OSTI ID:21254385

Clifton, Timothy ^[1]

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1. Department of Astrophysics, University of Oxford, Oxford, OX1 3RH (United Kingdom)

We consider the Friedmann-Robertson-Walker cosmologies of theories of gravity that generalize the Einstein-Hilbert action by replacing the Ricci scalar R with some function f(R). The general asymptotic behavior of these cosmologies is found, at both early and late times, and the effects of adding higher and lower powers of R to the Einstein-Hilbert action is investigated. The assumption that the highest powers of R should dominate the Universe's early history, and that the lowest powers should dominate its future is found to be inaccurate. The behavior of the general solution is complicated, and while it can be the case that single powers of R dominate the dynamics at late times, it can be either the higher or lower powers that do so. It is also shown that it is often the lowest powers of R that dominate at early times, when approach to a bounce or a Tolman solution are generic possibilities. Various examples are considered, and both vacuum and perfect fluid solutions are investigated.

• OSTI ID: 21254385
• Journal Information: Physical Review. D, Particles Fields, Journal Name: Physical Review. D, Particles Fields Journal Issue: 8 Vol. 78; ISSN PRVDAQ; ISSN 0556-2821
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
ASYMPTOTIC SOLUTIONS
COSMOLOGY
GRAVITATION
IDEAL FLOW
SIMULATION
UNIVERSE