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Testing massive-field modifications of gravity via gravitational waves

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 نشر من قبل Kei Yamada
 تاريخ النشر 2019
  مجال البحث فيزياء
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The direct detection of gravitational waves now provides a new channel of testing gravity theories. Despite that the parametrized post-Einsteinian framework is a powerful tool to quantitatively investigate effects of modification of gravity theory, the gravitational waveform in this framework is still extendable. One of such extensions is to take into account the gradual activation of dipole radiation due to massive fields, which are still only very weakly constrained if their mass $m$ is greater than $10^{-16}$ eV from pulsar observations. Ground-based gravitational-wave detectors, LIGO, Virgo, and KAGRA, are sensitive to this activation in the mass range, $10^{-14}$ eV $lesssim m lesssim 10^{-13}$ eV. Hence, we discuss a dedicated test for dipole radiation due to a massive field using the LIGO-Virgo collaborations open data. In addition, assuming Einstein-dilaton-Gauss-Bonnet (EdGB) type coupling, we combine the results of the analysis of the binary black hole events to obtain the 90% confidence level constraints on the coupling parameter $alpha_{rm EdGB}$ as $sqrt{alpha_{rm EdGB}} lesssim 2.47$ km for any mass less than $6 times 10^{-14}$ eV for the first time, including $sqrt{alpha_{rm EdGB}} lesssim 1.85$ km in the massless limit.



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