{
  "abstract": "We examine whether or not the current observational preference for a dynamical dark energy(DE), as reported by DESI, is an artifact of the chosen functional form of dark energy equation of state (EoS) parameter $w(z)$ by considering a higher-order quadratic extension in EoS. We explore three distinct parameterizations of the DE models: the two-parameter (linear) Chevallier-Polarski-Linder (CPL) and Wang models, alongside a three-parameter parabolic (quadratic) formulation. Using a joint dataset of CMB measurements from Planck and ACT DR6, baryon acoustic oscillations of DESI DR2, and Type Ia supernovae from Pantheon+ and DES-SN5YR, we constrain the model parameters and observe a maximum frequentist preference of up to $\\sim 4σ$ for these dynamical models. Specifically, the joint CMB + DESI + DES-SN5YR combination yields a substantial improvement in fit over $Λ\\text{CDM}$, with $Δχ^2_{\\text{min}}$ values of $-20.5$, $-19.4$, and $-21.7$ for CPL, Wang, and Parabolic models, respectively. In addition, the Akaike Information Criterion (AIC) provides weak to no evidence for $Λ$CDM, consistently favoring the dynamical DE models instead. On the other hand, the Bayesian Information Criterion (BIC) imposes a heavy penalty on all the three models, reflecting its high sensitivity to dataset size and model complexity. We find at best a mild support for CPL and Wang models but the Parabolic model is strongly disfavored ($Δ\\text{BIC} \\sim +6.4$ to $+15.6$). Furthermore, due to its expanded parameter space, the Parabolic model exhibits a significant reduction in the Figure of Merit (FoM) compared to the two-parameter counterparts, demonstrating that the current cosmological datasets do not yet justify an introduction of the higher-order DE models. So, as a result, the two-parameter descriptions of $w(z)$ remain the optimal choice for testing the dynamical DE signatures.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.02910",
  "author_total": 3,
  "authors": [
    {
      "name": "Laiphangbam Khumaba Mangang"
    },
    {
      "name": "Yumnam Prakash Singh"
    },
    {
      "name": "N. Chandrachani Devi"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2abg45havn3x0.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.02910",
  "fulltext_url": null,
  "id": "2abg45havn3x0",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.02910",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "physics.gen-ph"
    ],
    [
      "openalex",
      "3103|Cosmology and Gravitation Theories"
    ]
  ],
  "openalex": "W7208772533",
  "pdf_url": "https://arxiv.org/pdf/2609.02910",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2abg45havn3x0.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:18:31Z",
      "native_id": "2609.02910",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.02910"
    }
  ],
  "subjects": [
    {
      "field": "astronomy",
      "origin": "openalex:3103|Cosmology and Gravitation Theories",
      "subfield": "cosmology"
    }
  ],
  "title": "Examining the Linear and Quadratic Dark Energy Parameterizations with DESI DR2 via AIC and BIC Selection",
  "title_text": "Examining the Linear and Quadratic Dark Energy Parameterizations with DESI DR2 via AIC and BIC Selection",
  "type": "preprint",
  "updated_at": "2026-10-30T12:18:31Z",
  "url": "https://research.draconitic.com/paper/2abg45havn3x0",
  "venue": "arXiv",
  "versions": []
}