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arXiv · 1907.10858

Photon sphere and perihelion shift in weak $f(T)$ gravity

Sebastian Bahamonde·Kai Flathmann·Christian Pfeifer
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Abstract

Among modified theories of gravity, the teleparallel $f(T)$ gravity is an intensively discussed modelin the literature. The best way to investigate its viabilityis to derive observable predictions which yield evidence or constraints for the model, when compared with actual observations. In this paper we derive the photon sphere and the perihelion shift for weak $f(T)$ perturbations of general relativity. We consistently calculate first order teleparallel perturbations of Schwarzschild and Minkowski spacetime geometry, with which we improve and extend existing results in the literature.

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Sebastian Bahamonde, Kai Flathmann, Christian Pfeifer. 2019-07-25. Photon sphere and perihelion shift in weak $f(T)$ gravity. https://doi.org/10.1103/physrevd.100.084064

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