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arXiv · 2011.06303

Solar System Tests in Brans-Dicke and Palatini f(R)-theories

Alice Bonino·Stefano Camera·Lorenzo Fatibene·Andrea Orizzonte
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Abstract

We compare Mercury's precession test in standard General Relativity (GR), Brans-Dicke theories (BD), and Palatini f(R)-theories. We avoid post Newtonian (PN) approximation and compute exact precession in these theories. We show that the well-known mathematical equivalence between Palatini f(R)-theories and a specific subset of BD theories does not extend to a really physical equivalence among theories since equivalent models still allow different incompatible precession for Mercury depending on the solution one chooses. As a result one cannot use BD equivalence to rule out Palatini f(R)-theories. On the contrary, we directly discuss that Palatini f(R)-theories can (and specific models do) easily pass Solar System tests as Mercury's precession.

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Alice Bonino, Stefano Camera, Lorenzo Fatibene, Andrea Orizzonte. 2020-11-12. Solar System Tests in Brans-Dicke and Palatini f(R)-theories. https://doi.org/10.1140/epjp/s13360-020-00982-9

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