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arXiv · 2606.05358

The DESI results impact the local determination of $H_0$

Michael S. Turner·Dragan Huterer
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Abstract

Measurements of baryon acoustic oscillations (BAO) by the Dark Energy Spectroscopic Instrument (DESI) have revealed evidence for dark energy that evolves. If local distance measurements are analyzed with the $w_0w_a$ models preferred by the DESI measurements, the value for the Hubble constant can be as much as $2.5\,\mathrm{km\,s^{-1}Mpc^{-1}}$ smaller than the value obtained assuming $\Lambda$CDM. When these $w_0w_a$ models are further constrained by cosmic microwave background (CMB) and type Ia supernova (SNIa) data, the downward shift is $1.1 \pm 0.38\,\mathrm{km\,s^{-1}Mpc^{-1}}$ (DESI + CMB) and $0.5 \pm 0.1\,\mathrm{km\,s^{-1}Mpc^{-1}}$ (DESI + CMB + SNIa). The dependence of local determinations of $H_0$ on the background cosmology, combined with the fact that the low-redshift cosmology is not well constrained, is relevant to the Hubble tension.

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Michael S. Turner, Dragan Huterer. 2026-06-03. The DESI results impact the local determination of $H_0$. https://arxiv.org/abs/2606.05358

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