Examining Quintessence Models with DESI Data

Zahra Bayat; Mark P. Hertzberg

doi:10.1088/1475-7516/2025/08/065

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arXiv · 2505.18937

Examining Quintessence Models with DESI Data

Zahra Bayat·Mark P. Hertzberg

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Abstract

We examine data from the Dark Energy Spectroscopic Instrument (DESI) collaboration which has implications for the nature of dark energy. We consider classes of models that manifestly obey the null energy condition, with a focus on quintessence models. We find that hilltop potentials and exponential potentials provide modest improvement compared to a cosmological constant, but the statistical evidence is only marginal at this stage. We correct some analyses in the existing literature which attempted to compare some quintessence models to the data, giving an overly positive result.

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Zahra Bayat, Mark P. Hertzberg. 2025-05-25. Examining Quintessence Models with DESI Data. https://doi.org/10.1088/1475-7516%2F2025%2F08%2F065

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