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arXiv · 1701.05998

Polarizations of gravitational waves in $f(R)$ gravity

Dicong Liang·Yungui Gong·Shaoqi Hou·Yunqi Liu
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Abstract

We point out that there are only three polarizations for gravitational waves in $f(R)$ gravity, and the polarization due to the massive scalar mode is a mix of the pure longitudinal and transverse breathing polarization. The classification of the six polarizations by the Newman-Penrose quantities is based on weak, plane and null gravitational waves, so it is not applicable to the massive mode.

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Dicong Liang, Yungui Gong, Shaoqi Hou, Yunqi Liu. 2017-01-21. Polarizations of gravitational waves in $f(R)$ gravity. https://doi.org/10.1103/physrevd.95.104034

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