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arXiv · 2512.10585

Is Dark Energy Dynamical in the DESI Era? A Critical Review

Salvatore Capozziello·Himanshu Chaudhary·Tiberiu Harko·Ghulam Mustafa
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Abstract

We investigate whether the recent DESI DR2 measurements provide or not evidences for dynamical dark energy by exploring the $\omega_0\omega_a$CDM model and its extensions with free $\sum m_{\nu}$ and $N_{\mathrm{eff}}$. Using a comprehensive MCMC analysis with a wide range of cosmological datasets including DESI~DR2 BAO and Ly$\alpha$ data, CMB compressed likelihoods, BBN, cosmic chronometers, and multiple Type~Ia supernova compilations, we assess the statistical preference for departures from $\Lambda$CDM.

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Salvatore Capozziello, Himanshu Chaudhary, Tiberiu Harko, Ghulam Mustafa. 2025-12-11. Is Dark Energy Dynamical in the DESI Era? A Critical Review. https://doi.org/10.1016/j.dark.2025.102196

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