Cosmology and Nongalactic Astrophysics2025-07-29v3General Relativity and Quantum CosmologyHigh Energy Physics - PhenomenologyHigh Energy Physics - Theory
We demonstrate that a ∼2σ discrepancy with the Planck-ΛCDM cosmology in DESI Luminous Red Galaxy (LRG) data in the redshift range 0.4<z<0.6 with effective redshift zeff=0.51 translates into an unexpectedly large Ωm value, Ωm=0.67−0.17+0.18. We independently confirm that this anomaly drives the preference for w0>−1 in DESI data \textit{alone} confronted to the w0waCDM model. Given that LRG data at zeff=0.51 is at odds with Type Ia supernovae in overlapping redshifts, we expect that this anomaly will decrease in statistical significance with future DESI data releases leaving an increasing Ωm trend with effective redshift at higher redshifts. We estimate the current significance of the latter in DESI data at ∼1.8σ and comment on how it dovetails with independent observations. It is imperative to understand what makes DESI LRG data at zeff=0.51 an outlier when it comes to Ωm determinations.
Cite
@article{arxiv.2404.08633,
title = {Does DESI 2024 Confirm $\Lambda$CDM?},
author = {Eoin Ó Colgáin and Maria Giovanna Dainotti and Salvatore Capozziello and Saeed Pourojaghi and M. M. Sheikh-Jabbari and Dejan Stojkovic},
journal= {arXiv preprint arXiv:2404.08633},
year = {2025}
}
Comments
5 pages, 3 figures; v2 comments added, references updated; v3 to appear in JHEAP