Dynamical Dark Energy in light of DESI BAO and Full-Shape Data

Quan Zhou; Sibo Zheng

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arXiv · 2512.07104

Dynamical Dark Energy in light of DESI BAO and Full-Shape Data

Quan Zhou·Sibo Zheng

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Abstract

Recently, the DESI BAO data has reported a preference of dynamical dark energy (DDE) over the \LambdaCDM cosmology. Apart from the BAO data, the DDE model should be also sensitive to low-redshift measurements of the matter power spectrum data. In this study, we address this point by combining the DESI Y1 data about the matter power spectrum, extracted from the DESI Full-Shape data, with the DESI DR2 BAO data among other probes. After building the DESI Y1 likelihood, we carry out a Markov Chain Monte Carlo analysis, showing that the constraints on $w_0$ and $w_a$ with DESI Y1 data included are improved over those without it for three different datasets widely considered, especially in the case of the DESY5 sample.

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Quan Zhou, Sibo Zheng. 2025-12-08. Dynamical Dark Energy in light of DESI BAO and Full-Shape Data. https://arxiv.org/abs/2512.07104

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