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arXiv · 2107.02889

How a conformally flat (GR)4 impacts Gauss-Bonnet gravity?

Avik De·Tee-How Loo·Raja Solanki·P. K. Sahoo
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Abstract

First and foremost, we show that a 4-dimensional conformally flat generalized Ricci recurrent spacetime $(GR)_4$ is an Einstein manifold. We examine such a spacetime as a solution of $f(R, G)$-gravity theory and it is shown that the additional terms from the modification of the gravitational sector can be expressed as a perfect fluid. Several energy conditions are investigated with $f(R, G) = R +\sqrt{G}$ and $f(R, G) = R^2+GlnG$. For both the models, weak, null and dominant energy conditions are satisfied while strong energy condition is violated, which is a good agreement with the recent observational studies which reveals that the current universe is in accelerating phase.

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Avik De, Tee-How Loo, Raja Solanki, P. K. Sahoo. 2021-07-05. How a conformally flat (GR)4 impacts Gauss-Bonnet gravity?. https://doi.org/10.1002/prop.202100088

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