2025/02/14 by Agripino Sousa-Neto, Sousa-Neto, Agripino, Carlos A. P. Bengaly +5 · 3 citations
Biochemistry, Genetics and Molecular Biology · Economics, Econometrics and Finance · Physics and Astronomy · #Complex Systems and Time Series Analysis #Cosmology and Gravitation Theories #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Fractal and DNA sequence analysis #General Relativity and Quantum Cosmology (gr-qc)
paper · pdf · doi:10.48550/arxiv.2502.10506
openalex publication_date 2025/02/14 · openalex created_date 2025/02/19 · openalex updated_date 2026/07/28
Recent measurements of Baryon Acoustic Oscillations (BAO) from the Dark Energy Spectroscopic Survey (DESI DR2), combined with data from the cosmic microwave background (CMB) and Type Ia supernovae (SNe), challenge the Λ-Cold Dark Matter (ΛCDM) paradigm. They indicate a potential evolution in the dark energy equation of state (EoS), w(z), as suggested by analyses that employ parametric models. In this paper, we use a model-independent approach known as high performance symbolic regression (PySR) to reconstruct w(z) directly from observational data, allowing us to bypass prior assumptions about the underlying cosmological model. Our findings confirm that the DESI DR2 data alone agree with the ΛCDM model (w(z) = -1) at the redshift range considered. Additionally, when combining DESI data with existing compilations of SN distance measurements, such as Patheon+ and DESY5, we observe no deviation from the ΛCDM model within 3σ (C.L.) for the interval of values of present-day matter density parameter Ωm and the sound horizon at the drag epoch rd currently constrained by observational data. Therefore, similarly to the DESI DR1 case, these results suggest that it is still premature to claim statistically significant evidence for a dynamical EoS or deviations from the ΛCDM model based on the current DESI data in combination with supernova measurements.