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arXiv · 0805.1241

On the non-minimal gravitational coupling to matter

O. Bertolami·J. Páramos
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Abstract

The connection between $f(R)$ theories of gravity and scalar-tensor models with a "physical" metric coupled to the scalar field is well known. In this work, we pursue the equivalence between a suitable scalar theory and a model that generalises the $f(R)$ scenario, encompassing both a non-trivial scalar curvature term and a non-minimum coupling of the scalar curvature and matter. This equivalence allows for the calculation of the PPN parameters $β$ and $γ$ and, eventually, a solution to the debate concerning the weak-field limit of $f(R)$ theories.

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O. Bertolami, J. Páramos. 2008-08-04. On the non-minimal gravitational coupling to matter. https://doi.org/10.1088/0264-9381%2F25%2F24%2F245017

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