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相关论文: Comparison of dynamical dark energy with {\Lambda}…

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We study the late-time cosmological dynamics of a two-field dark energy model consisting of a canonical quintessence scalar field and a phantom scalar field in a spatially flat FLRW universe. The fields are minimally coupled to gravity and…

宇宙学与河外天体物理 · 物理学 2026-01-06 Phusuda Thanankullaphong , Prasanta Sahoo , Prajwal Hassan Puttasiddappa , Nandan Roy

We compute the Bayesian evidences for one- and two-parameter models of evolving dark energy, and compare them to the evidence for a cosmological constant, using current data from Type Ia supernova, baryon acoustic oscillations, and the…

天体物理学 · 物理学 2008-11-26 Andrew R Liddle , Pia Mukherjee , David Parkinson , Yun Wang

In this paper, we employ two model-independent approaches, including redshift binning method and polynomial interpolation method, to reconstruct dark energy (DE) equation of state (EoS) $w(z)$ and DE density function $f(z)$. Our analysis…

宇宙学与河外天体物理 · 物理学 2025-11-18 Jun-Xian Li , Shuang Wang

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…

宇宙学与河外天体物理 · 物理学 2010-05-11 Hong Li , Jun-Qing Xia

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.…

宇宙学与河外天体物理 · 物理学 2026-04-17 Matilde L. Abreu , Michael S. Turner

Recent cosmological measurements are hinting that dark energy may evolve, with its equation of state, $w_\mathrm{DE}$, even showing oscillatory patterns. In this work, we employ a model-independent approach to jointly reconstruct…

宇宙学与河外天体物理 · 物理学 2025-12-19 Pietro Ghedini , Rasmi Hajjar , Olga Mena

We study 6 LCDM models, with 4 allowing for non-flat geometry and 3 allowing for a non-unity lensing consistency parameter $A_L$. We also study 6 XCDM models with a dynamical dark energy density X-fluid with equation of state $w$. For the…

宇宙学与河外天体物理 · 物理学 2024-06-05 Javier de Cruz Perez , Chan-Gyung Park , Bharat Ratra

We investigate the Dark Scattering (DS) interacting dark energy scenario, characterised by pure momentum exchange between dark matter and dark energy, combined with a time-dependent equation-of-state for dark energy described by the…

宇宙学与河外天体物理 · 物理学 2026-05-14 M. Tsedrik , B. Bose

We reconstruct evolution of the dark energy (DE) density using a nonparametric Bayesian approach from a combination of latest observational data. We caution against parameterizing DE in terms of its equation of state as it can be singular…

宇宙学与河外天体物理 · 物理学 2018-12-12 Yuting Wang , Levon Pogosian , Gong-Bo Zhao , Alex Zucca

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…

宇宙学与河外天体物理 · 物理学 2025-08-12 Jincheng Wang , Hongwei Yu , Puxun Wu

We reconstruct dark energy properties from two complementary supernova datasets -- the newly released Gold+HST sample and SNLS. The results obtained are consistent with standard $\Lambda$CDM model within $2\sigma$ error bars although the…

天体物理学 · 物理学 2010-10-27 Ujjaini Alam , Varun Sahni , Alexei A. Starobinsky

We investigate constraints on some key cosmological parameters by confronting metastable dark energy models with different combinations of the most recent cosmological observations. Along with the standard $\Lambda$CDM model, two…

宇宙学与河外天体物理 · 物理学 2020-01-14 Xiaolei Li , Arman Shafieloo , Varun Sahni , Alexei A. Starobinsky

Recent data from DESI Year 2 BAO, Planck CMB, and various supernova compilations suggest a preference for evolving dark energy, with hints that the equation of state may cross the phantom divide line ($w = -1$). While this behavior is seen…

宇宙学与河外天体物理 · 物理学 2025-06-19 Ryan E. Keeley , Arman Shafieloo , William L. Matthewson

Baryon acoustic oscillation (BAO) data from the Dark Energy Spectroscopic Instrument (DESI) appear to indicate the first evidence for dynamical dark energy (DDE), with a present-day behavior resembling quintessence. This evidence emerges…

宇宙学与河外天体物理 · 物理学 2025-04-08 Felipe Bruno Medeiros dos Santos , Jonathan Morais , Supriya Pan , Weiqiang Yang , Eleonora Di Valentino

In this work, we present a study on cosmological constraints of dark energy (DE) parametrizations after the observations of Dark Energy Spectroscopic Instruments (DESI) for Baryon Acoustic Oscillations (BAO) in 2024, suggesting potential…

宇宙学与河外天体物理 · 物理学 2025-04-07 M. Malekjani , Z. Davari , S. Pourojaghi

Cosmological models exhibiting crossing of the phantom divide improve the fit to current data, suggesting late-time dark energy (DE) dynamics at $\sim3\sigma$ CL. However, they favor low values of $H_0$, in tension with SH0ES. This may…

宇宙学与河外天体物理 · 物理学 2026-05-27 Alex González-Fuentes , Adrià Gómez-Valent

We perform fits to DESI, CMB and supernova data to understand the physical origin of the DESI hint for dynamical dark energy. We find that the linear parametrization of the equation of state $w$ may guide to misleading interpretations, such…

宇宙学与河外天体物理 · 物理学 2025-02-27 Ioannis D. Gialamas , Gert Hütsi , Kristjan Kannike , Antonio Racioppi , Martti Raidal , Martin Vasar , Hardi Veermäe

To explore whether there is new physics going beyond the standard cosmological model or not, we constrain seven cosmological models by combining the latest and largest Pantheon Type Ia supernovae sample with the data combination of baryonic…

宇宙学与河外天体物理 · 物理学 2018-06-13 Deng Wang

The phenomenological parametrizations of dark-energy (DE) equation of state can be very helpful, since they allow for the investigation of its cosmological behavior despite the fact that its underlying theory is unknown. However, although…

宇宙学与河外天体物理 · 物理学 2019-03-06 Weiqiang Yang , Supriya Pan , Eleonora Di Valentino , Emmanuel N. Saridakis , Subenoy Chakraborty

Motivated by the recent baryon acoustic oscillation measurements of DESI DR2 collaboration, this works presents an extended analysis of a cosmological model based on holographic dark energy within the framework of Unimodular Gravity. We…

宇宙学与河外天体物理 · 物理学 2025-11-13 Francisco Plaza , Gabriel León , Lucila Kraiselburd