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Gravitational-wave cosmography with LISA and the Hubble tension

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 نشر من قبل Koutarou Kyutoku
 تاريخ النشر 2016
  مجال البحث فيزياء
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We propose that stellar-mass binary black holes like GW150914 will become a tool to explore the local Universe within ~100Mpc in the era of the Laser Interferometer Space Antenna (LISA). High calibration accuracy and annual motion of LISA could enable us to localize up to ~60 binaries more accurately than the error volume of ~100Mpc^3 without electromagnetic counterparts under moderately optimistic assumptions. This accuracy will give us a fair chance to determine the host object solely by gravitational waves. By combining the luminosity distance extracted from gravitational waves with the cosmological redshift determined from the host, the local value of the Hubble parameter will be determined up to a few % without relying on the empirically constructed distance ladder. Gravitational-wave cosmography would pave the way for resolution of the disputed Hubble tension, where the local and global measurements disagree in the value of the Hubble parameter at 3.4sigma level, which amounts to ~9%.



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