Testing inhomogeneous cosmography in our cosmic neighborhood using CosmicFlows-4
arXiv:2412.12637 · doi:10.1103/6z7w-47rc
Abstract
The convergence of the third order general cosmographic expansion of the luminosity distance is examined using several versions of a semi-realistic model of our local cosmic neighborhood, based on publicly available density and velocity fields from CosmicFlows-4. The study supports earlier findings that the general cosmographic expansion diverges at surprisingly low redshifts, often well before z = 0.1. By being based on a realistically placed observer within a data-informed cosmic environment, the results underscore that convergence must be a central concern when applying the general cosmographic expansion. By showing all-sky maps of kinematic parameters, the study also highlights the substantial information we lose when relying solely on standard FLRW-based cosmography. Poor convergence does not necessarily render the information extracted by fitting data to the general cosmographic expansion meaningless. Rather, it calls for caution in interpreting this information, particularly regarding the physical meaning of the fitting coefficients, the physical scales they probe and the implicit smoothing introduced by the fit.
arXiv commentSubmitted to PRD. v2: Analysis significantly extended but no changes in overall conclusions. 21 pages. Matches version accepted for publication in PRD. v3: Minor clarifying note (footnote 2) added after publication. No changes to results or conclusions
References in corpus (39)
- SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
- Array Programming with NumPy
- Astropy: A Community Python Package for Astronomy
- The Astropy Project: Building an inclusive, open-science project and status of the v2.0 core package
- HEALPix -- a Framework for High Resolution Discretization, and Fast Analysis of Data Distributed on the Sphere
- The Astropy Project: Sustaining and Growing a Community-oriented Open-source Project and the Latest Major Release (v5.0) of the Core Package
- The Einstein Toolkit: A Community Computational Infrastructure for Relativistic Astrophysics
- The Hubble series: Convergence properties and redshift variables
- A Challenge to the Standard Cosmological Model
- gevolution: a cosmological N-body code based on General Relativity
- Cosmicflows-4
- Light Propagation in Arbitrary Spacetimes and the Gravitational Lens Approximation
- Newtonian and Relativistic Cosmologies
- Analyzing the Large-Scale Bulk Flow using CosmicFlows4: Increasing Tension with the Standard Cosmological Model
- Cosmological Applications of Pade Approximant
- The peculiar velocity field up to by forward-modeling Cosmicflows-3 data
- Anti-lensing: the bright side of voids
- Effect of Peculiar Motion in Weak Lensing
- Testing the Cosmological Principle with CatWISE Quasars: A Bayesian Analysis of the Number-Count Dipole
- Multipole decomposition of the general luminosity distance 'Hubble law' -- a new framework for observational cosmology
- Is backreaction really small within concordance cosmology?
- Is there really a Hubble tension?
- The cosmic radio dipole: Bayesian estimators on new and old radio surveys
- Gravity in the Local Universe : density and velocity fields using CosmicFlows-4
- Luminosity distance and anisotropic sky-sampling at low redshifts: a numerical relativity study
- Studying the precision of ray tracing techniques with Szekeres models
- Methods for studying the accuracy of light propagation in N-body simulations
- Identification of Basins of Attraction in the Local Universe
- Covariant cosmography: the observer-dependence of the Hubble parameter
- Testing cosmic anisotropy with Pade approximation and Pantheon+ sample
- Testing the isotropy of cosmic acceleration with Pantheon+ and SH0ES: A cosmographic analysis
- Cosmography of the Local Universe by Multipole Analysis of the Expansion Rate Fluctuation Field
- Consistency of Pantheon+ supernovae with a large-scale isotropic universe
- Observing relativistic features in large-scale structure surveys -- II: Doppler magnification in an ensemble of relativistic simulations
- Cosmological distances with general-relativistic ray tracing: framework and comparison to cosmographic predictions
- Towards Cosmography of the Local Universe
- Expanding covariant cosmography of the local Universe: incorporating the snap and axial symmetry
- On the convergence of cosmographic expansions in Lemaitre-Tolman-Bondi models
- Anisotropy in the cosmic acceleration inferred from supernovae