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arXiv · 1204.6273

f(R) and f(T) theories of modified gravity

Rafael Ferraro
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Abstract

We briefly review f(R) theories, both in the metric and Palatini formulations, their scalar-tensor representations and the chameleon mechanism that could explain the absence of perceptible consequences in the Solar System. We also review f(T) theories, a different approach to modified gravity consisting in a deformation of the teleparallel equivalent of General Relativity. We show some applications to cosmology and cosmic strings. As f(R)'s, f(T) theories are not exempted from additional degrees of freedom; we also discuss this still open issue.

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Rafael Ferraro. 2012-05-03. f(R) and f(T) theories of modified gravity. https://doi.org/10.1063/1.4756821

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