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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 $\Lambda$-Cold Dark…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-16 Agripino Sousa-Neto , Carlos Bengaly , Javier E. Gonzalez , Jailson Alcaniz

In this study, we explore the impact of various combinations of CMB-independent datasets, including the recent DESI BAO measurements, on the equation of state (EoS) of dark energy and other cosmological parameters within the framework of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-13 Manisg Yadav , Archana Dixit , M. S. Barak , Anirudh Pradhan

We revisit a cosmological model where dark matter (DM) and dark energy (DE) follow barotropic equations of state, allowing deviations from the standard $\Lambda$CDM framework (i.e. $w_{dm} \neq 0$, $w_{de} \neq -1$), considering both flat…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-24 Dorian Araya , Cristian Castillo , Genly Leon , Juan Magaña , Angie Barr Domínguez , Miguel A. García-Aspeitia

The DESI collaboration have recently analyzed their first year of data, finding a preference for thawing dark energy scenarios when using parameterized equations of state for dark energy. We investigate whether this preference persists when…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-30 Omar F. Ramadan , Jeremy Sakstein , David Rubin

A fundamental question in cosmology is whether dark energy evolves over time, a topic that has gained prominence since the discovery of cosmic acceleration. Recently, the DESI collaboration has reported increasing evidence for evolving dark…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-21 Deng Wang , David Mota

Baryonic Acoustic Oscillation (BAO) data from the Dark Energy Spectroscopic Instrument (DESI), in combination with Cosmic Microwave Background (CMB) data and Type Ia Supernovae (SN) luminosity distances, suggests a dynamical evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-03 João Rebouças , Diogo H. F. de Souza , Kunhao Zhong , Vivian Miranda , Rogerio Rosenfeld

This article discusses a dark energy cosmological model in the standard theory of gravity - general relativity with a broad scalar field as a source. Exact solutions of Einstein's field equations are derived by considering a particular form…

General Relativity and Quantum Cosmology · Physics 2022-08-23 S. K. J. Pacif , Simran Arora , P. K. Sahoo

The Dark Energy Spectroscopic Instrument (DESI) collaboration has recently released measurements of baryon acoustic oscillation (BAO) from the first year of observations. A joint analysis of DESI BAO, CMB, and SN Ia probes indicates a…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-02 Anton Chudaykin , Martin Kunz

We present a Dark Energy (DE) model with a sound derivation as a natural extension of the Standard Model of particle physics with no free parameters and an excellent fit with current cosmological data improving by 21% the $\Lambda$CDM fit…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-24 A. de la Macorra , E. Almaraz

We explore a phenomenological model of dark energy in which space is treated as an elastic brane with uniform tension $T_s$ and supports a longitudinal phonon sector described by three scalar fields $\phi^I$. At the background level the…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-30 Muhammad Ghulam Khuwajah Khan

This study explores the possibility of a time-varying dark energy (DE) equation of state (EoS) deviating from -1. We employ a comprehensive dataset of usual astronomical probes (Type Ia supernovae, baryon acoustic oscillations, Big Bang…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-23 Mehdi Rezaei , Supriya Pan , Weiqiang Yang , David F. Mota

In this article, we investigate a new parametrization of the dark energy equation of state (EoS) with a single parameter for a barotropic fluid that deviates from the standard $\Lambda$CDM cosmology. We derive observational constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-31 D. Revanth Kumar , Santosh Kumar Yadav

This manuscript revisits the phenomenological emergent dark energy model (PEDE) by confronting it with recent cosmological data from early and late times. In particular we analyze PEDE model by using the baryon acoustic oscillation (BAO)…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-11 A. Hernández-Almada , M. L. Mendoza-Martínez , Miguel A. García-Aspeitia , V. Motta

Recently, the measurements of baryon acoustic oscillations (BAO) by the Dark Energy Spectroscopic Instrument (DESI) indicate a potential deviation from the standard $\Lambda$CDM model. Some studies suggest that the data points from the…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-21 Jie Zheng , Da-Chun Qiang , Zhi-Qiang You

Recent Baryon Acoustic Oscillation (BAO) measurements released by DESI, when combined with Cosmic Microwave Background (CMB) data from Planck and two different samples of Type Ia supernovae (Pantheon-Plus and DESY5) reveal a preference for…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-11 William Giarè , Mahdi Najafi , Supriya Pan , Eleonora Di Valentino , Javad T. Firouzjaee

We conduct a Bayesian analysis of recent observational datasets, specifically the Cosmic Chronometers (CC) dataset and Pantheon samples, to investigate the evolution of the EoS parameter in dark energy models. Our study focused on the…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-29 N. Myrzakulov , M. Koussour , Alnadhief H. A. Alfedeel , Amare Abebe

We investigate a dark energy (DE) equation of state (EoS) parametrization in a curved spacetime using current observations. We constrain the model parameters by using observational Hubble data from Cosmic Chronometer (CC), Pantheon Plus…

General Physics · Physics 2026-05-13 D. Revanth Kumar , Santosh Kumar Yadav

The latest results on baryon acoustic oscillations from DESI (Dark Energy Spectroscopic Instrument), when combined with cosmic microwave background and supernova data, show indications of a deviation from a cosmological constant in favour…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-17 Marina Cortês , Andrew R Liddle

Theories of evolving quintessence are constructed that generically lead to deviations from the w = -1 prediction of non-evolving dark energy. The small mass scale that governs evolution, m_\phi \approx 10^{-33} eV, is radiatively stable,…

Astrophysics · Physics 2009-09-29 Lawrence J. Hall , Yasunori Nomura , Steven J. Oliver