New DESI Data Confirms Universe's Large-Scale Homogeneity, Supporting Standard Cosmological Model
Researchers using data from the Dark Energy Spectroscopic Instrument (DESI) measured the angular homogeneity scale of the universe and found it consistent with the Lambda-CDM cosmological model. The study tested the Cosmological Principle—the assumption that the universe is statistically uniform on large scales—by analyzing the distribution of luminous red galaxies across different regions of sky. The findings reinforce a foundational assumption underlying modern cosmology and validate predictions for future large-scale surveys.
A new analysis of DESI Data Release 1 has measured the angular homogeneity scale (θ_H) of the universe using observations of luminous red galaxies across redshift ranges from 0.4 to 1.1. The researchers conducted their analysis in two dimensions across narrow redshift slices in both the North and South Galactic Caps to minimize dependence on pre-existing cosmological assumptions. The measured homogeneity scales were consistent across all redshift ranges, between the two sky regions, and with previous measurements from SDSS-IV eBOSS data, as well as with predictions from Lambda-CDM mock simulations. These results provide observational support for the Cosmological Principle—one of the two foundational pillars of the standard model alongside General Relativity—which posits that the universe is statistically homogeneous and isotropic on sufficiently large scales. The consistency of findings across independent datasets and sky regions strengthens confidence in this assumption as cosmology enters the era of stage-IV redshift surveys.
What different sources said
- arXiv astro-phCenter
$\delta$-CDM: A Minimal Deformation of $\Lambda$CDM with Scalar Field Reconstruction
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