Gravitational Lensing and f(R) theories in the Palatini approach

Matteo Luca Ruggiero

doi:10.1007/s1071400807172 10.1007/s10714-008-0717-2

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arXiv · 0712.3218

Gravitational Lensing and f(R) theories in the Palatini approach

Matteo Luca Ruggiero

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Abstract

We investigate gravitational lensing in the Palatini approach to the f(R) extended theories of gravity. Starting from an exact solution of the f(R) field equations, which corresponds to the Schwarzschild-de Sitter metric and, on the basis of recent studies on this metric, we focus on some lensing observables, in order to evaluate the effects of the non linearity of the gravity Lagrangian. We give estimates for some astrophysical events, and show that these effects are tiny for galactic lenses, but become interesting for extragalactic ones.

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Matteo Luca Ruggiero. 2008-11-03. Gravitational Lensing and f(R) theories in the Palatini approach. https://doi.org/10.1007/s1071400807172%2010.1007%2Fs10714-008-0717-2

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