Results 91 to 100 of about 170,764 (173)

The Excess of JWST Bright Galaxies: A Possible Origin in the Ground State of Dynamical Dark Energy in the Light of DESI 2024 Data

The Astrophysical Journal
Recent observations by JWST yield a large abundance of luminous galaxies at z ≳ 10 compared to that expected in the ΛCDM scenario based on extrapolations of the star formation efficiency measured at lower redshifts.
N. Menci, A. A. Sen, M. Castellano
doaj   +1 more source

Constraining Cosmological Parameters Using the Splashback Radius of Galaxy Clusters

The Astrophysical Journal
Cosmological parameters such as Ω _M and σ _8 can be measured indirectly using various methods, including galaxy cluster abundance and cosmic shear. These measurements constrain the composite parameter S _8 , leading to degeneracy between Ω _M and σ _8 .
Roan Haggar, Yuba Amoura, Charlie T. Mpetha, James E. Taylor, Kris Walker, Chris Power   +5 more
doaj   +1 more source

Is Dark Energy Changing? Probing the Universe’s Expansion with Present and Future Astronomical Probes

The Astrophysical Journal
This study explores the possibility of a time-varying dark energy (DE) equation of state (EoS) deviating from −1. We employ a comprehensive data set of the usual astronomical probes (Type Ia supernovae, baryon acoustic oscillations, Big Bang ...
Mehdi Rezaei, Supriya Pan, Weiqiang Yang, David F. Mota   +3 more
doaj   +1 more source

Mapping the Λ_sCDM Scenario to f(T) Modified Gravity: Effects on Structure Growth Rate

Universe
The concept of a rapidly sign-switching cosmological constant, interpreted as a mirror AdS-dS transition in the late universe and known as the ΛsCDM, has significantly improved the fit to observational data, offering a promising framework for alleviating
Mateus S. Souza, Ana M. Barcelos, Rafael C. Nunes, Özgür Akarsu, Suresh Kumar   +4 more
doaj   +1 more source

Beyond Two Parameters: Revisiting Dark Energy with the Latest Cosmic Probes

The Astrophysical Journal
Dark energy (DE) models with many free parameters are often considered excessive, as constraining all parameters poses a significant challenge. While such models offer greater flexibility to probe the DE sector in more detail.
Hanyu Cheng, Supriya Pan, Eleonora Di Valentino   +2 more
doaj   +1 more source

Hints of New Physics for the Hubble Tension: Violation of Cosmological Principle

The Astrophysical Journal Letters
Discrepancy between the measurements of Hubble constant H _0 from the cosmic microwave background and the local distance ladder is the most serious challenge to the standard ΛCDM model.
J. P. Hu, X. D. Jia, J. Hu, F. Y. Wang
doaj   +1 more source

Cascading Dark Energy

The Astrophysical Journal
The standard cosmological model is in the midst of a stress test, thanks to the tension between supernova-based measurements of the Hubble constant H _0 and inferences of its values from cosmic microwave background (CMB) anisotropies.
Kazem Rezazadeh, Amjad Ashoorioon, Daniel Grin   +2 more
doaj   +1 more source

Analytic Calculation of Covariance between Cosmological Parameters from Correlated Data Sets, with an Application to SPTpol. [PDF]

Astrophys J, 2020
Kable JA, Addison GE, Bennett CL.
europepmc   +1 more source

The Cosmological Parameters 2010

, 2010
25 pages TeX file. Article for The Review of Particle Physics 2010 (aka the Particle Data Book), on-line version at http://pdg.lbl.gov/ .
Lahav, Ofer, Liddle, Andrew R
openaire   +2 more sources

Hubble-constant and -mass determination of Centaurus A and M83 from tip-of-red-giant-branch distances

Astronomy & Astrophysics
An independent determination of the Hubble constant is crucial in light of the persistent tension between early- and late-Universe measurements. In this study, we analysed the dynamics of the Centaurus A (CenA) and M83 galaxies, along with their ...
Faucher Adrian, Benisty David, Mota David F.   +2 more
doaj   +1 more source