Probing departures from $Λ$CDM by late-time datasets

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Chaudhary, Himanshu, Sharma, Vipin Kumar, Capozziello, Salvatore, Mustafa, G.
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866911602283905024
author Chaudhary, Himanshu
Sharma, Vipin Kumar
Capozziello, Salvatore
Mustafa, G.
author_facet Chaudhary, Himanshu
Sharma, Vipin Kumar
Capozziello, Salvatore
Mustafa, G.
contents Observational data play a pivotal role in identifying cosmological models that are both theoretically consistent and empirically viable. In this work, we investigate the level of preference for dynamical dark energy over a cosmological constant using current late-time observational datasets, including Cosmic Chronometers , Baryon Acoustic Oscillations from DESI DR2, and different Type Ia supernova catalogs (Pantheon$^+$, DES-Dovekie, Union3). We analyze various dynamical dark energy models, including $ω$CDM, o$ω$CDM, $ω_0ω_a$CDM, Logarithmic, Exponential, JBP, BA, and GEDE. In most cases, the o$Λ$CDM and o$ω$CDM models favor an open Universe. For the o$ω$CDM, the inclusion of DES-Dovekie or Union3 data together with CC and DESI DR2 favors a nearly flat geometry. Using the CC + DESI DR2 dataset, the preference for dynamical dark energy lies between the $1$-$2σ$ level. When different supernova catalogs (DES-Dovekie or Union3) are included, the deviation from $Λ$CDM in the $ω$CDM, $ω_0ω_a$CDM, Logarithmic, JBP, BA, and GEDE models increases to the $2$-$2.74σ$ level, while the Pantheon$^{+}$ sample yields deviations below the $2σ$ level. We find consistent evidence for $ω_0 > -1$ and $ω_a < 0$ across all dark energy models, indicating a preference for dynamical dark energy characterized by a Quintom-B type scenario. The $Λ$CDM paradigm has long served as the standard framework of modern cosmology; however recent DESI DR2 results have exposed emerging tensions with the cosmological constant $Λ$, hinting at possible new physics in the dark energy sector. Even so, the currently available data are still not strong enough to definitively rule out the $Λ$CDM model.
format Preprint
id arxiv_https___arxiv_org_abs_2510_08339
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Probing departures from $Λ$CDM by late-time datasets
Chaudhary, Himanshu
Sharma, Vipin Kumar
Capozziello, Salvatore
Mustafa, G.
Cosmology and Nongalactic Astrophysics
General Relativity and Quantum Cosmology
High Energy Physics - Theory
Observational data play a pivotal role in identifying cosmological models that are both theoretically consistent and empirically viable. In this work, we investigate the level of preference for dynamical dark energy over a cosmological constant using current late-time observational datasets, including Cosmic Chronometers , Baryon Acoustic Oscillations from DESI DR2, and different Type Ia supernova catalogs (Pantheon$^+$, DES-Dovekie, Union3). We analyze various dynamical dark energy models, including $ω$CDM, o$ω$CDM, $ω_0ω_a$CDM, Logarithmic, Exponential, JBP, BA, and GEDE. In most cases, the o$Λ$CDM and o$ω$CDM models favor an open Universe. For the o$ω$CDM, the inclusion of DES-Dovekie or Union3 data together with CC and DESI DR2 favors a nearly flat geometry. Using the CC + DESI DR2 dataset, the preference for dynamical dark energy lies between the $1$-$2σ$ level. When different supernova catalogs (DES-Dovekie or Union3) are included, the deviation from $Λ$CDM in the $ω$CDM, $ω_0ω_a$CDM, Logarithmic, JBP, BA, and GEDE models increases to the $2$-$2.74σ$ level, while the Pantheon$^{+}$ sample yields deviations below the $2σ$ level. We find consistent evidence for $ω_0 > -1$ and $ω_a < 0$ across all dark energy models, indicating a preference for dynamical dark energy characterized by a Quintom-B type scenario. The $Λ$CDM paradigm has long served as the standard framework of modern cosmology; however recent DESI DR2 results have exposed emerging tensions with the cosmological constant $Λ$, hinting at possible new physics in the dark energy sector. Even so, the currently available data are still not strong enough to definitively rule out the $Λ$CDM model.
title Probing departures from $Λ$CDM by late-time datasets
topic Cosmology and Nongalactic Astrophysics
General Relativity and Quantum Cosmology
High Energy Physics - Theory
url https://arxiv.org/abs/2510.08339