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arXiv · 1108.2900

On Shear-free perturbations of f(R) gravity

Amare Abebe·Rituparno Goswami·Peter K. S. Dunsby
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Abstract

Recently it was shown that if the matter congruence of a general relativistic perfect fluid flow in an almost FLRW universe is shear-free, then it must be either expansion or rotation-free. Here we generalize this result for a general f(R) theory of gravity and show there exist scenarios where this result can be avoided. This suggests that there are situations where linearized forth-order gravity shares properties with Newtonian theory not valid in General Relativity.

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Amare Abebe, Rituparno Goswami, Peter K. S. Dunsby. 2011-08-14. On Shear-free perturbations of f(R) gravity. https://doi.org/10.1103/physrevd.84.124027

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