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Related papers: Oscillations in the dark energy EoS: new MCMC less…

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While there is mounting evidence in all fronts of experimental cosmology for a non-vanishing dark energy component in the Universe, we are still far away from understanding its ultimate nature. A fundamental cosmological constant, Lambda,…

Astrophysics · Physics 2008-11-26 Joan Sola , Hrvoje Stefancic

The equation of state (EoS) of dark energy plays an important role in the evolution of the universe and arouses great interests in recent years. With the progress on observational technique, precise constraint on the EoS of dark energy…

General Relativity and Quantum Cosmology · Physics 2019-08-19 Hai-Nan Lin , Xin Li , Li Tang

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

In this paper, we study the new Tsallis agegraghic dark energy model in the context of fractal cosmology. The different cosmic implications such as statefinder diagnosis, cosmological plane and squared of sound speed in both interacting and…

General Relativity and Quantum Cosmology · Physics 2024-01-17 M. Abdollahi Zadeh

We derive multiple constraints on dark energy and compare dynamical dark energy models with a time-varying equation of state ($w_0 w_a$CDM) versus a cosmological constant model ($\Lambda$CDM). We use Baryon Acoustic Oscillation (BAO) from…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-24 Mustapha Ishak , Leonel Medina-Varela

Baryon acoustic oscillation (BAO) is one of the important standard rulers in cosmology. The results of the latest BAO measurements by Dark Energy Spectroscopic Instrument (DESI) survey have been reported. Cosmology with the varying electron…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-23 Osamu Seto , Yo Toda

We show that the baryonic oscillations expected in the galaxy power spectrum may be used as a "standard cosmological ruler'' to facilitate accurate measurement of the cosmological equation of state. Our approach involves a straight-forward…

Astrophysics · Physics 2008-11-26 Chris Blake , Karl Glazebrook

Combined measurements of Baryon Acoustic Oscillations (BAO) from the Dark Energy Spectroscopic Survey (DESI), the Cosmic Microwave Background (CMB) and Type Ia Supernovae (SN Ia), have recently challenged the $\Lambda$-Cold Dark Matter…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-10 Rayff de Souza , Agripino Sousa-Neto , Javier E. González , Jailson Alcaniz

Here we test different models of dark energy beyond the standard cosmological constant scenario. We start considering the CPL parameterization of the equation of state (EOS), then we consider a dark energy scalar field (Quintessense).…

High Energy Astrophysical Phenomena · Physics 2018-02-07 Marek Demianski , Ester Piedipalumbo , Disha Sawant , Lorenzo Amati

Recent observations from the DESI survey have reignited the debate on the true nature of dark energy, challenging the standard model of cosmology. The results suggest a preference for dynamical dark energy rather than a constant. Several…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-28 Ramanpreet Singh , Athul CN , H. K. Jassal

We present strong evidence for dynamical dark energy that challenges the standard $\Lambda$CDM model. Several dark energy scenarios are explored, including $\omega_0\omega_a$CDM, logarithmic, exponential, JBP, and BA parameterizations,…

General Relativity and Quantum Cosmology · Physics 2025-11-18 Himanshu Chaudhary , Salvatore Capozziello , Subhrat Praharaj , Shibesh Kumar Jas Pacif , G. Mustafa

Observations with NASA's Rossi X-ray Timing Explorer (RXTE) have resulted in the discovery of fast (200 - 600 Hz), coherent X-ray intensity oscillations (hereafter, "burst oscillations") during thermonuclear X-ray bursts from 12 low mass…

Astrophysics · Physics 2009-11-10 Tod E. Strohmayer

In this paper, we combine the the latest observational data, including the WMAP five-year data (WMAP5), the baryon acoustic oscillations (BAO) and type Ia supernovae (SN) "union" compilation, and use the Markov Chain Monte Carlo method to…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-11 Hong Li , Jun-Qing Xia

We detail a novel theoretical prediction that a geometric torsion model for scalar field dark matter could lead to oscillations, on readily probeable timescales, in the time evolution of cosmological redshifts of astronomical sources with…

General Relativity and Quantum Cosmology · Physics 2023-02-20 James Wheeler

The frequencies and damping times of the non radial oscillations of neutron stars are computed for a set of recently proposed equations of state (EOS) which describe matter at supranuclear densites. These EOS are obtained within two…

Astrophysics · Physics 2009-11-10 O. Benhar , V. Ferrari , L. Gualtieri

Recent observational results from the DESI collaboration reveal tensions with the standard $\Lambda$CDM model and favour a scenario in which dark energy (DE) decays over time. The DESI DR2 data also suggest that the DE equation of state…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-29 Swagat S. Mishra , William L. Matthewson , Varun Sahni , Arman Shafieloo , Yuri Shtanov

In the last year, several pieces of evidence have pointed to a possible deviation from the standard cosmological model, $\Lambda$CDM. The recent work by the Dark Energy Survey (DES) collaboration reports a preference in the ballpark of…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-13 Santiago Avila , Juan Mena-Fernández , Maria Vincenzi

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

It is well known that there are several long-standing problems implying the discordance of the $\Lambda$CDM model. Although most of the models proposed to resolve these problems assume that dark matter is pressureless, it is still possible…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-31 Yan-Hong Yao , Jun-Chao Wang , Xin-He Meng

This paper explores the dark energy phenomenon within the context of $f(R,L_m)$ gravity theory. Two specific non-linear $f (R, L_m)$ models are considered: $f(R,L_m)=\frac{R}{2}+L_m^\alpha$ and $f(R,L_m)=\frac{R}{2}+(1+\alpha R)L_m$, where…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-13 S. Myrzakulova , M. Koussour , N. Myrzakulov