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arXiv · 1812.00938

Linear cosmological perturbations in almost scale-invariant fourth-order gravity

Jorge L. Fuentes·Usman A. Gillani·Karim A. Malik
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Abstract

We study a class of almost scale-invariant modified gravity theories, using a particular form of $f(R, G) = \alpha R^2 + \beta G \log G$ where $R$ and $G$ are the Ricci and Gauss-Bonnet scalars, respectively and $\alpha$, $\beta$ are arbitrary constants. We derive the Einstein-like field equations to first order in cosmological perturbation theory in longitudinal gauge.

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Jorge L. Fuentes, Usman A. Gillani, Karim A. Malik. 2018-12-03. Linear cosmological perturbations in almost scale-invariant fourth-order gravity. https://arxiv.org/abs/1812.00938

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