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arXiv · gr-qc/9811013

Cosmological perturbations in a gravity with quadratic order curvature couplings

H. Noh·J. Hwang
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Abstract

We present a set of equations describing the evolution of the scalar-type cosmological perturbation in a gravity with general quadratic order curvature coupling terms. Equations are presented in a gauge ready form, thus are ready to implement various temporal gauge conditions depending on the problems. The Ricci-curvature square term leads to a fourth-order differential equation for describing the spacetime fluctuations in a spatially homogeneous and isotropic cosmological background.

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H. Noh, J. Hwang. 1998-11-04. Cosmological perturbations in a gravity with quadratic order curvature couplings. https://doi.org/10.1103/physrevd.59.047501

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