Expected redshift drift for tilted observers

Abstract

Redshift drift is usually discussed for observers comoving with the cosmological background, but realistic observations are made by observers with nonzero peculiar motion. In this work, we calculate the expected redshift drift for tilted observers within the covariant 1+3 formalism. Starting from the exact redshift measured in the tilted frame, we derive the corresponding drift as an FLRW background term plus a directional correction driven by the observer's peculiar kinematics, encoded through peculiar expansion, projected shear, and projected acceleration along the line of sight. We analyse first an Einstein--de Sitter (EdS) background, which isolates the purely kinematic effect of tilt in the absence of background acceleration, and then extend the calculation to $\Lambda$CDM in order to quantify how the same anisotropic corrections deform the standard drift signal in the concordance model.

17 pages, 2 (+2) figures. Improved version with minor changes and added references. Accepted in EPJC

References in corpus (32)

• Planck 2018 results. I. Overview and the cosmological legacy of Planck
• DESI 2024 VI: Cosmological Constraints from the Measurements of Baryon Acoustic Oscillations
• Challenges for $\Lambda$CDM: An update
• Cosmicflows-2: The Data
• Cosmicflows-3
• Consistently Large Cosmic Flows on Scales of 100 Mpc/h: a Challenge for the Standard LCDM Cosmology
• A measurement of large-scale peculiar velocities of clusters of galaxies: results and cosmological implications
• A Test of the Cosmological Principle with Quasars
• Relativistic cosmology and large-scale structure
• A new measurement of the bulk flow of X-ray luminous clusters of galaxies
• The 6dF Galaxy Survey: Peculiar Velocity Field and Cosmography
• Cosmicflows-4
• Cosmological implications of the anisotropy of ten galaxy cluster scaling relations
• Analyzing the Large-Scale Bulk Flow using CosmicFlows4: Increasing Tension with the Standard Cosmological Model
• 2MTF I. The Tully-Fisher Relation in the 2MASS J, H and K Bands
• On Larger $H_0$ Values in the CMB Dipole Direction
• Observational constraints on the deceleration parameter in a tilted universe
• The time evolution of cosmological redshift as a test of dark energy
• The 6dF Galaxy Survey: Fundamental Plane Data
• The Road to Precision Cosmology
• Another look at redshift drift and the backreaction conjecture
• The Statistical Significance of the "Dark Flow"
• Large-scale Cosmic Flows from Cosmicflows-2 Catalog
• 2MTF - VII. 2MASS Tully-Fisher survey final data release: distances for 2,062 nearby spiral galaxies
• The peculiar Raychaudhuri equation
• On the Statistical Significance of the Bulk Flow Measured by the PLANCK Satellite
• The deceleration parameter in `tilted' universes: generalising the Friedmann background
• Anisotropy in Pantheon+ supernovae
• Testing anisotropic Hubble expansion
• Approximations for the divergence of the local large-scale structure velocity field and its implications for Tilted Cosmology
• Redshift drift in a universe with structure III: Numerical relativity
• The 2MASS Tully-Fisher Survey : Mapping the Mass in the Universe