Cosmological constraints on non-cold dark matter from DESI DR2 measurements
- 1Department of Physics, University of Ottawa, Ottawa, ON K1N6N5, Canada
- 2Indian Institute of Science Education and Research Bhopal, Bhopal 462066, India
- 3Physics Department, Ariel University, Ariel 40700, Israel
Abstract
We investigate potential deviations from cold dark matter (CDM) using the latest Baryon Acoustic Oscillations (BAO) measurements from the Dark Energy Spectroscopic Instrument (DESI). Analyzing DESI data alone constrains the dark matter equation of state parameter w dm = − 0 . 042 − 0.024 + 0.047 , revealing a mild preference for non-cold dark matter. This preference strengthens significantly in combined analyses, but reveals a striking tension in the inferred w dm values from observations of different nature. The DESI+DESY5 combination yields w dm = − 0.084 ± 0.035 , excluding CDM ( w dm = 0 ) at 2.4 σ significance. In contrast, Planck+DESI gives w dm = 0.00077 ± 0.00038 , differing from concordance model at 2 σ significance. The non-vanishing w dm preference is particularly driven by low-redshift BAO measurements ( z < 1.1), while higher redshift data remain consistent with ΛCDM. The preference for non-cold dark matter is more pronounced in DESI compared to the previous BAO surveys. All dataset combinations show significant improvement over the ΛCDM paradigm, providing preference for non-cold dark matter scenario except DESI+DESY3+DES-DOV case.
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BibTeX
@article{kumar2026cosmological,
title = {{Cosmological constraints on non-cold dark matter from DESI DR2 measurements}},
author = {Utkarsh Kumar and Abhijith Ajith and Amresh Verma},
journal = {Physics Letters B},
year = {2026},
month = aug,
doi = {10.1016/j.physletb.2026.140858},
url = {https://doi.org/10.1016/j.physletb.2026.140858},
note = {CC BY},
}
RIS
TY - JOUR
TI - Cosmological constraints on non-cold dark matter from DESI DR2 measurements
AU - Utkarsh Kumar
AU - Abhijith Ajith
AU - Amresh Verma
PY - 2026
DA - 2026/08/15
JO - Physics Letters B
DO - 10.1016/j.physletb.2026.140858
UR - https://doi.org/10.1016/j.physletb.2026.140858
AB - We investigate potential deviations from cold dark matter (CDM) using the latest Baryon Acoustic Oscillations (BAO) measurements from the Dark Energy Spectroscopic Instrument (DESI). Analyzing DESI data alone constrains the dark matter equation of state parameter w dm = − 0 . 042 − 0.024 + 0.047 , revealing a mild preference for non-cold dark matter. This preference strengthens significantly in combined analyses, but reveals a striking tension in the inferred w dm values from observations of different nature. The DESI+DESY5 combination yields w dm = − 0.084 ± 0.035 , excluding CDM ( w dm = 0 ) at 2.4 σ significance. In contrast, Planck+DESI gives w dm = 0.00077 ± 0.00038 , differing from concordance model at 2 σ significance. The non-vanishing w dm preference is particularly driven by low-redshift BAO measurements ( z < 1.1), while higher redshift data remain consistent with ΛCDM. The preference for non-cold dark matter is more pronounced in DESI compared to the previous BAO surveys. All dataset combinations show significant improvement over the ΛCDM paradigm, providing preference for non-cold dark matter scenario except DESI+DESY3+DES-DOV case.
SN - 0370-2693
SN - 1873-2445
ER -