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arXiv · 2504.06290

A DESI universe with time-dependent dark energy is 119 Myr younger than a LambdaCDM universe

Kevin Cahill
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Abstract

On the basis of their redshift and Lyman-alpha measurements, the Dark Energy Spectroscopic Instrument (DESI) collaboration suggest that dark energy varies with the scale factor $a$ as $ \rho_{de}(a)={} \, a^{-3(1 + w_0 + w_a)} e^{-3 w_a (1-a)}\rho_{de,0} $ in which $w_0 = - 0.752 \pm 0.057$ and $w_a ={} - 0.86^{+0.23}_{-0.20} $. Such a DESI universe is 119 Myr younger than the LambdaCDM universe.

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Kevin Cahill. 2025-04-04. A DESI universe with time-dependent dark energy is 119 Myr younger than a LambdaCDM universe. https://arxiv.org/abs/2504.06290

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