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Constraining f(R) Gravity as a Scalar Tensor Theory

Thomas Faulkner·Max Tegmark·Emory F. Bunn·Yi Mao
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Abstract

We search for viable f(R) theories of gravity, making use of the equivalence between such theories and scalar-tensor gravity. We find that models can be made consistent with solar system constraints either by giving the scalar a high mass or by exploiting the so-called chameleon effect. However, in both cases, it appears likely that any late-time cosmic acceleration will be observationally indistinguishable from acceleration caused by a cosmological constant. We also explore further observational constraints from, e.g., big bang nucleosynthesis and inflation.

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Thomas Faulkner, Max Tegmark, Emory F. Bunn, Yi Mao. 2006-12-20. Constraining f(R) Gravity as a Scalar Tensor Theory. https://doi.org/10.1103/physrevd.76.063505

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