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arXiv · gr-qc/9610059

Cosmological Gravitational Wave 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 cosmological gravitational wave in a gravity theory with quadratic order gravitational coupling terms which naturally arise in quantum correction procedures. It is known that the gravitational wave equation in the gravity theories with a general $f(R)$ term in the action leads to a second order differential equation with the only correction factor appearing in the damping term. The case for a $R^{ab} R_{ab}$ term is completely different. The gravitational wave is described by a fourth order differential equation both in time and space. However, curiously, we find that the contributions to the background evolution are qualitatively the same for both terms.

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H. Noh, J. Hwang. 1996-10-25. Cosmological Gravitational Wave in a Gravity with Quadratic Order Curvature Couplings. https://doi.org/10.1103/physrevd.55.5222

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