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Related papers: Shape of Dark Energy: Constraining Its Evolution w…

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We present limits on the parameters of the o$\Lambda$CDM, $w_0$CDM, and $w_0 w_a$CDM models obtained from the joint analysis of the full-shape, baryon acoustic oscillations (BAO), big bang nucleosynthesis (BBN) and supernovae data. Our…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-16 Anton Chudaykin , Konstantin Dolgikh , Mikhail M. Ivanov

We investigate how strongly late-time inferences about DE dynamics depend on the functional prior used to represent the expansion history. Using identical late-time combinations of CC, DESI BAO measurements, the Pantheon+ SN1a sample, and…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-15 Özgür Akarsu , Maria Caruana , Konstantinos F. Dialektopoulos , Luis A. Escamilla , Emre O. Kahya , Jackson Levi Said

We investigate the observational consequences of a novel class of stable interacting dark energy (IDE) models, featuring interactions between dark matter (DM) and dark energy (DE). In the first part of our work, we start by considering two…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-13 Weiqiang Yang , Supriya Pan , Eleonora Di Valentino , Rafael C. Nunes , Sunny Vagnozzi , David F. Mota

We propose a two parameter generalization for the dark energy equation of state (EOS) $w_X$ for thawing dark energy models which includes PNGB, CPL and Algebraic thawing models as limiting cases and confront our model with the latest…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-09 Debabrata Adak , Debasish Majumdar , Supratik Pal

In this paper we investigate a new phenomenological parameterization for unified dark matter and dark energy based on the polynomial expansion of the barotropic equation of state parameter $w$. Our parameterization provides well-behaving…

General Relativity and Quantum Cosmology · Physics 2018-08-01 Zahra Davari , Mohammad Malekjani , Michal Artymowski

We introduce a new parametrization for the dark energy, led by the same idea to the linear expansion of the equation of state in scale factor $a$ and in redshift $z$, which diverges neither in the past nor future and contains the same…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-01 Ozgur Akarsu , Tekin Dereli , J. Alberto Vazquez

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

The Planck collaboration has recently published maps of the Cosmic Microwave Background radiation with the highest precision. In the standard flat $\Lambda$CDM framework, Planck data show that the Hubble constant $H_0$ is in tension with…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-04 Jun-Qing Xia , Hong Li , Xinmin Zhang

Any Dark Energy (DE) or Modified Gravity (MG) model that deviates from a cosmological constant requires a consistent treatment of its perturbations, which can be described in terms of an effective entropy perturbation and an anisotropic…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-26 Bjoern Soergel , Tommaso Giannantonio , Jochen Weller , Richard A. Battye

We apply a new non-parametric Bayesian method for reconstructing the evolution history of the equation-of-state $w$ of dark energy, based on applying a correlated prior for $w(z)$, to a collection of cosmological data. We combine the latest…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-20 Gong-Bo Zhao , Robert G. Crittenden , Levon Pogosian , Xinmin Zhang

We revisit the evolution of cosmic acceleration in a spatially flat $w_0w_a$CDM universe, in which the equation of state of dark energy takes the CPL parametrization, using the latest baryon acoustic oscillation (BAO) measurements from the…

Cosmology and Nongalactic Astrophysics · Physics 2025-08-12 Jincheng Wang , Hongwei Yu , Puxun Wu

We propose a novel dark-energy equation-of-state parametrization, with a single parameter $\eta$ that quantifies the deviation from $\Lambda$CDM cosmology. We first confront the scenario with various datasets, from Hubble function (OHD),…

General Relativity and Quantum Cosmology · Physics 2024-06-04 J. K. Singh , Preeti Singh , Emmanuel N. Saridakis , Shynaray Myrzakul , Harshna Balhara

We explore the cosmological constraints on the parameter w_dm of the dark matter barotropic equation of state (EoS) to investigate the "warmness" of the dark matter fluid. The model is composed by the dark matter and dark energy fluids in…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-21 Arturo Avelino , Norman Cruz , Ulises Nucamendi

A puzzling implication of current data interpreted in the $\Lambda$CDM cosmology is the preference for a negative sum of neutrino masses. Moving to $w_0w_a$CDM brings an appreciable fraction of the neutrino mass posterior back to positive…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-17 Weiqiang Yang , Eleonora Di Valentino , Eric V. Linder , Sibo Zhang , Supriya Pan

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

We reconstruct the effective Equation of State (EoS) within the framework of General Relativity (GR) theory in a homogeneous and isotropic FLRW Universe, which is assumed to be composed of matter and Dark Energy (DE). Our analysis employs a…

General Relativity and Quantum Cosmology · Physics 2023-09-29 N. Myrzakulov , M. Koussour , Alnadhief H. A. Alfedeel , E. I. Hassan

In this paper, we study the cosmological implications of the 100 square degree Weak Lensing survey (the CFHTLS-Wide, RCS, VIRMOS-DESCART and GaBoDS surveys). We combine these weak lensing data with the cosmic microwave background (CMB)…

Astrophysics · Physics 2010-05-07 Hong Li , Jie Liu , Jun-Qing Xia , Lei Sun , Zu-Hui Fan , Charling Tao , Andre Tilquin , Xinmin Zhang

In this paper, we investigate the impact of the lensing anomaly in Planck cosmic microwave background (CMB) data on the nature of dark energy (DE). We constrain the state equation ($w_0,w_a$) of DE with the lensing scaling parameter $A_L=1$…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-19 Ze-Yu Peng , Yun-Song Piao

The first and second year results of DESI provide consistent evidence that dark energy may not be quantum vacuum energy ($\Lambda$). If true, this would be an extraordinary development in the 25-year quest to understand cosmic acceleration.…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-17 Matilde L. Abreu , Michael S. Turner

In this study, we investigate the oscillatory dark energy model $w_{\sin}\mathrm{CDM}$ based on the DESI BAO data together with OHD, Pantheon Plus, and SH0ES measurements. We examine how the DESI data influence the dark energy…

General Physics · Physics 2026-02-06 Manish Yadav , Archana Dixit , M. S. Barak , Anirudh Pradhan