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

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.

5 pages, 2 figures, accepted by PRL

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Cited by in corpus (16)

• Is the Observable Universe Consistent with the Cosmological Principle?
• On the Possibility of Anisotropic Curvature in Cosmology
• Is there further evidence for spatial variation of fundamental constants?
• Anisotropic dark energy and ellipsoidal universe
• Another look at redshift drift and the backreaction conjecture
• Bianchi I meets the Hubble diagram
• Cosmic Parallax in Ellipsoidal Universe
• Cosmic Parallax as a probe of late time anisotropic expansion
• The Averaging Problem in Cosmology
• Redshift drift cosmography for model-independent cosmological inference
• Spatial and temporal tuning in void models for acceleration
• BiGONLight: light propagation with bi-local operators in Numerical Relativity
• Kinematic Distortions of the High-Redshift Universe as Seen from Quasar Proper Motions
• Algebraic symmetries of the observables on the sky: Variable emitters and observers
• A Quantitative Framework for Testing the Hubble Tension in a Bianchi Type I Cosmological Background
• Power of photonic states: from quantum computation to cosmology