Simulations forecast that 10 years of Einstein Telescope and Cosmic Explorer data could detect the cosmic dipole magnitude using strongly lensed GW events, with tighter bounds from combining double, triple, and quadruple lensed systems.
Singal,Large peculiar motion of the solar system from the dipole anisotropy in sky brightness due to distant radio sources,The Astrophysical Journal742(2011) L23 [1110.6260]
4 Pith papers cite this work. Polarity classification is still indexing.
abstract
According to the cosmological principle, the Universe should appear isotropic, without any preferred directions, to an observer whom we may consider to be fixed in the co-moving co-ordinate system of the expanding Universe. Such an observer is stationary with respect to the average distribution of the matter in the Universe and the sky brightness at any frequency should appear uniform in all directions to such an observer. However a peculiar motion of such an observer, due to a combined effect of Doppler boosting and aberration, will introduce a dipole anisotropy in the observed sky brightness; in reverse an observed dipole anisotropy in the sky brightness could be used to infer the peculiar velocity of the observer with respect to the average Universe. We determine the peculiar velocity of the solar system relative to the frame of distant radio sources, by studying the anisotropy in the sky brightness from discrete radio sources, i.e., an integrated emission from discrete sources per unit solid angle. Our results give a direction of the velocity vector in agreement with the Cosmic Microwave Background Radiation (CMBR) value, but the magnitude ($\sim 1600\pm 400$ km/s) is $\sim 4$ times the CMBR value ($369\pm 1$ km/s) at a statistically significant ($\sim 3\sigma$) level. A genuine difference between the two dipoles would imply anisotropic Universe, with the anisotropy changing with the epoch. This would violate the cosmological principle where the isotropy of the Universe is assumed for all epochs, and on which the whole modern cosmology is based upon.
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The cosmic dipole anomaly detected in quasars remains significant after generalizing the kinematic link to observer velocity beyond power-law luminosity and spectral assumptions.
Kinetic Sunyaev-Zel'dovich reconstruction from WISExSuperCOSMOS and unWISE galaxies with Planck data yields tight upper limits on bulk velocities consistent with LambdaCDM out to 2000 h^{-1} Mpc while showing tension with a quasar dipole interpretation.
No evidence for directional anisotropy in the cosmic distance duality relation is found, yielding a robust 95% upper bound of 0.025 on the dipole amplitude after accounting for survey selection effects.
citing papers explorer
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Prospect of Measuring the Cosmic Dipole by Strongly Lensed Gravitational Waves Associated with Galaxy Surveys
Simulations forecast that 10 years of Einstein Telescope and Cosmic Explorer data could detect the cosmic dipole magnitude using strongly lensed GW events, with tighter bounds from combining double, triple, and quadruple lensed systems.
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The kinematic cosmic dipole beyond Ellis and Baldwin
The cosmic dipole anomaly detected in quasars remains significant after generalizing the kinematic link to observer velocity beyond power-law luminosity and spectral assumptions.
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Measuring cosmic bulk flow with kinetic Sunyaev-Zel'dovich velocity reconstruction
Kinetic Sunyaev-Zel'dovich reconstruction from WISExSuperCOSMOS and unWISE galaxies with Planck data yields tight upper limits on bulk velocities consistent with LambdaCDM out to 2000 h^{-1} Mpc while showing tension with a quasar dipole interpretation.
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Directional Tests of the Cosmic Distance Duality Relation using Pantheon+ and BAO
No evidence for directional anisotropy in the cosmic distance duality relation is found, yielding a robust 95% upper bound of 0.025 on the dipole amplitude after accounting for survey selection effects.