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تسجيل مستخدم جديدLinear cosmological perturbations in almost scale-invariant fourth-order gravity
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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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