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arXiv · gr-qc/0603071

Fourth order gravity and experimental constraints on Eddington parameters

S. Capozziello·A. Stabile·A. Troisi
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Abstract

PPN-limit of higher order theories of gravity represents a still controversial matter of debate and no definitive answer has been provided, up to now, about this issue. By exploiting the analogy between scalar-tensor and fourth-order theories of gravity, one can generalize the PPN-limit formulation. By using the definition of the PPN-parameters $γ$ and $β$ in term of the $f(R)$ derivatives, we show that a family of third-order polynomial theories, in the Ricci scalar $R$, turns out to be compatible with the PPN-limit and the deviation from General Relativity theoretically predicted agree with experimental data.

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S. Capozziello, A. Stabile, A. Troisi. 2006-09-11. Fourth order gravity and experimental constraints on Eddington parameters. https://doi.org/10.1142/s0217732306021633

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