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Related papers: Uplifting, Depressing, and Tilting Dark Energy

200 papers

We present a Bayesian comparative analysis of five cosmological models: $\Lambda$CDM, $w$CDM, $w_0w_a$CDM, $\phi$CDM (with scalar-field dark energy), and an interacting dark energy scenario (the $\xi$-index model), to investigate dark…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-19 Zhuoming Zhang , Tengpeng Xu , Yun Chen

Observing dark energy dynamics is the most important aspect of the dark energy research. In this paper we perform an analysis of the constraints on the property of dark energy from the current astronomical observations. We pay particular…

Astrophysics · Physics 2009-11-13 Jun-Qing Xia , Gong-Bo Zhao , Bo Feng , Hong Li , Xinmin Zhang

The high-quality cosmological data, which became available in the last decade, have thrusted upon us a rather preposterous composition for the universe which poses one of the greatest challenges theoretical physics has ever faced: the…

Astrophysics · Physics 2015-06-24 J. S. Alcaniz

A huge amount of good quality astrophysical data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision…

Astrophysics · Physics 2009-06-23 S. Capozziello

Unless some unknown symmetry in Nature prevents or suppresses a non-minimal coupling in the dark sector, the dark energy field may interact with the pressureless component of dark matter. In this paper, we investigate some cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-28 F. E. M. Costa , E. M. Barboza , J. S. Alcaniz

While $\Lambda$CDM provides a good fit to cosmological data, it fails to address many of the outstanding questions in contemporary cosmology. Chief among these are the Hubble tension and the apparent dynamical nature of dark energy as…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-28 Amin Aboubrahim , Pran Nath

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

In this study, we use a flexible parametrization of the equation of state of dark energy to explore its possible evolution with datasets from the Dark Energy Spectroscopic Instrument (DESI), Planck cosmic microwave background, and either…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-14 Ryan E. Keeley , Kevork N. Abazajian , Manoj Kaplinghat , Arman Shafieloo

The consideration of dark energy's quanta, required also by thermodynamics, introduces its chemical potential into the cosmological equations. Isolating its main contribution, we obtain solutions with dark energy decaying to matter or…

Astrophysics · Physics 2008-11-26 J. Besprosvany

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

Dark energy, the enigmatic force driving the accelerated cosmic expansion of the universe, is conventionally described as a cosmological constant in the standard $\Lambda$CDM model. However, measurements from the Dark Energy Spectroscopic…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-26 Axel de la Macorra , Jose Agustin Lozano Torres

We report the constraints on the dark energy equation-of-state w(z) using the latest 'Constitution' SNe sample combined with the WMAP5 and SDSS data. Based on the localized principal component analysis and the model selection criteria, we…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-30 Gong-Bo Zhao , Xinmin Zhang

By studying the present cosmological data, particularly on CMB, SNeIA and LSS, we find that the future fate of the universe, for simple linear models of the dark energy equation-of-state, can vary between the extremes of (I) a divergence of…

Astrophysics · Physics 2009-11-10 Paul H. Frampton

A flat Friedman-Roberson-Walker universe dominated by a cosmological constant ($\Lambda$) and cold dark matter (CDM) has been the working model preferred by cosmologists since the discovery of cosmic acceleration. However, tensions of…

Late-time cosmic acceleration is one of the most interesting unsolved puzzles in modern cosmology. The explanation most accepted nowadays, dark energy, raises questions about its own nature, e.g. what exactly is dark energy, and…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-26 Williams J. M. Ribeiro

Full suite of the present day Cosmic Microwave background (CMB) data, when combined with weak prior information on the Hubble constant and the age of the Universe, or the Large-Scale structure, provides strong indication for a non-zero…

Astrophysics · Physics 2007-05-23 D. Pogosyan , J. R. Bond , C. R. Contaldi

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

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 examine the validity of the $\Lambda$CDM model, and probe for the dynamics of dark energy using latest astronomical observations. Using the $Om(z)$ diagnosis, we find that different kinds of observational data are in tension within the…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-14 Yuecheng Zhang , Hanyu Zhang , Dandan Wang , Yanghan Qi , Yuting Wang , Gong-Bo Zhao

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