中文
相关论文

相关论文: Deviation from $\Lambda$CDM: Pressure Parametrizat…

200 篇论文

Cosmological observations of the recent universe suggest that dark energy equation of state parameter $w$ is growing with time, departing from a cosmological constant for which $w=-1$. Standard quintessence models allow for a varying…

高能物理 - 理论 · 物理学 2025-07-11 David Andriot

A huge amount of good quality 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 Cosmology. Despite…

广义相对论与量子宇宙学 · 物理学 2008-12-02 S. Capozziello

We explore the effects of a positive cosmological constant on astrophysical and cosmological configurations described by a polytropic equation of state. We derive the conditions for equilibrium and stability of such configurations and…

天体物理学 · 物理学 2008-11-26 Andres Balaguera-Antolinez , David F. Mota , Marek Nowakowski

The $\Lambda$ cold dark matter ($\Lambda\textrm{CDM}$) model is currently known as the simplest cosmology model that best describes observations with minimal number of parameters. Here we introduce a cosmology model that is preferred over…

宇宙学与河外天体物理 · 物理学 2015-03-05 Chan-Gyung Park

The standard cosmological model is in the midst of a stress test, thanks to the tension between supernovae-based measurements of the Hubble constant $H_{0}$ and inferences of its values from Cosmic Microwave Background (CMB) anisotropies.…

宇宙学与河外天体物理 · 物理学 2024-11-05 K. Rezazadeh , A. Ashoorioon , D. Grin

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…

宇宙学与河外天体物理 · 物理学 2025-07-14 Ryan E. Keeley , Kevork N. Abazajian , Manoj Kaplinghat , Arman Shafieloo

Recent results regarding dark energy are mutually inconsistent under the $\Lambda$CDM cosmological model, hinting at the possibility of undiscovered physics. However, the currently accepted cosmological parameters come from a joint…

宇宙学与河外天体物理 · 物理学 2025-04-08 Charles L. Steinhardt , Preston Phillips , Radoslaw Wojtak

The measurements of the Hubble parameter using the cosmic microwave background radiation appear to be inconsistent with the measurements of this parameter using Cepheid variable stars. This inconsistency may be a result of using the…

综合物理 · 物理学 2021-01-25 Nikodem J. Popławski

The recent observational evidence for the current cosmic acceleration have stimulated renewed interest in alternative cosmologies, such as scenarios with interaction in the dark sector (dark matter and dark energy). In general, such models…

宇宙学与河外天体物理 · 物理学 2009-10-22 R. S. Goncalves , J. S. Alcaniz , A. Dev , D. Jain

The possibility of linking inflation and late cosmic accelerated expansion using the $\alpha$-attractor models has received increasing attention due to their physical motivation. In the early universe, $\alpha$-attractors provide an…

宇宙学与河外天体物理 · 物理学 2018-08-21 Carlos García-García , Eric V. Linder , Pilar Ruíz-Lapuente , Miguel Zumalacárregui

A dual component made of non-relativistic particles and a scalar field, exchanging energy, naturally falls onto an attractor solution, making them a (sub)dominant part of the cosmic energy during the radiation dominated era, provided that…

宇宙学与河外天体物理 · 物理学 2012-08-15 Silvio A. Bonometto , Giandomenico Sassi , Giuseppe La Vacca

We bring forward a generalized pressure dark energy (GPDE) model to explore the evolution of the universe. This model has covered three common pressure parameterization types and can be reconstructed as quintessence and phantom scalar…

宇宙学与河外天体物理 · 物理学 2019-10-23 Jun-Chao Wang , Xin-He Meng

Decaying Dark Energy models modify the background evolution of the most common observables, such as the Hubble function, the luminosity distance and the Cosmic Microwave Background temperature-redshift scaling relation. We use the most…

宇宙学与河外天体物理 · 物理学 2018-09-05 Ivan de Martino

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…

宇宙学与河外天体物理 · 物理学 2019-04-26 Williams J. M. Ribeiro

We study how observationally to distinguish between a cosmological constant (CC) and an evolving dark energy with equation of state $\omega(Z)$. We focus on the value of redshift Z* at which the cosmic late time acceleration begins and…

高能物理 - 理论 · 物理学 2015-05-27 Paul H. Frampton , Kevin J. Ludwick

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…

宇宙学与河外天体物理 · 物理学 2024-05-31 Yan-Hong Yao , Jun-Chao Wang , Xin-He Meng

The canonical cosmological model to explain the recent acceleration of the universe relies on a cosmological constant, and most dynamical dark energy and modified gravity model alternatives are based on scalar fields. Still, further…

宇宙学与河外天体物理 · 物理学 2025-02-10 C. S. C. M. Coelho , A. -L. Y. Gschrey , C. J. A. P. Martins

We discuss variants of Cold Dark Matter (CDM) dominated cosmological models that give good agreement with a range of observations. We consider models with hot dark matter, tilt, $\Omega < 1$, or a cosmological constant. We also discuss the…

天体物理学 · 物理学 2007-05-23 Rachel S. Somerville , Joel R. Primack

Promptly after high-resolution experiments harbinger the field of precision cosmology low- and high-redshift observations abruptly gave rise to a tension in the measurement of the present-day expansion rate of the Universe ($H_0$) and the…

宇宙学与河外天体物理 · 物理学 2024-11-08 Luis A. Anchordoqui , Ignatios Antoniadis , Dieter Lust , Neena T. Noble , Jorge F. Soriano

We discuss a new method which is potentially capable of constraining cosmological parameters using observations of giant luminous arcs in rich X-ray clusters of galaxies. The mass profile and the mass normalization of the lenses are…

天体物理学 · 物理学 2009-11-10 M. Sereno , G. Longo