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arXiv · 0809.3675

Cosmic Parallax: possibility of detecting anisotropic expansion of the universe by very accurate astrometry measurements

Claudia Quercellini·Miguel Quartin·Luca Amendola
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Abstract

Refined astrometry measurements allow us to detect large-scale deviations from isotropy through real-time observations of changes in the angular separation between sources at cosmic distances. This "cosmic parallax" effect is a powerful consistency test of FRW metric and may set independent constraints on cosmic anisotropy. We apply this novel general test to LTB cosmologies with off-center observers and show that future satellite missions such as Gaia might achieve accuracies that would put limits on the off-center distance which are competitive with CMB dipole constraints.

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Claudia Quercellini, Miguel Quartin, Luca Amendola. 2009-04-02. Cosmic Parallax: possibility of detecting anisotropic expansion of the universe by very accurate astrometry measurements. https://doi.org/10.1103/physrevlett.102.151302

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