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

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 نشر من قبل Yungui Gong
 تاريخ النشر 2017
  مجال البحث فيزياء
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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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