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Understanding the evolution of dark energy poses a significant challenge in modern cosmology, as it is responsible for the universe's accelerated expansion. In this study, we focus on a specific $f(T)$ cosmological model and analyze its…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-14 A. Zhadyranova , M. Koussour , S. Bekkhozhayev , V. Zhumabekova , J. Rayimbaev

The newly released observational $H(z)$ data (OHD) is used to constrain $\Lambda(t)$CDM models as holographic and agegraphic dark energy. By the use of the length scale and time scale as the IR cut-off including Hubble horizon (HH), future…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-13 Zhong-Xu Zhai , Tong-Jie Zhang , Wen-Biao Liu

The existence of a dark energy component has usually been invoked as the most plausible way to explain the recent observational results. However, it is also well known that effects arising from new physics (e.g., extra dimensions) can mimic…

Astrophysics · Physics 2009-11-10 J. S. Alcaniz , Abha Dev , Deepak Jain

High redshift supernovae and Cosmic Microwave Background data are used to constrain the Cardassian expansion model (Freese & Lewis 2002), a cosmology in which a modification to the Friedmann equation gives rise to a flat, matter-dominated…

Astrophysics · Physics 2009-11-10 W. J. Frith

Directly comparing the 6 expansion rate measured by type Ia supernovae data and the lower bound on the expansion rate set by the strong energy conditions or the null hypothesis that there never exists cosmic acceleration, we see $3\sigma$…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-06 Yingjie Yang , Yungui Gong

Cosmic acceleration is one of the most remarkable cosmological findings of recent years. Although a dark energy component has usually been invoked as the mechanism for the acceleration, A modification of Friedmann equation from various…

Astrophysics · Physics 2009-11-10 Zong-Hong Zhu , Masa-Katsu Fujimoto

The age of the universe is obtained in a subset of Cardassian models by using WMAP data. Cardassian expansion is a modification to the Friedmann equation that allows the universe to be flat, matter dominated, and accelerating, without a…

Astrophysics · Physics 2016-08-30 Christopher Savage , Noriyuki Sugiyama , Katherine Freese

In our study, we have adopted the framework of Horava-Lifshitz gravity to model the Universe's dark matter and dark energy components. Specifically, we have considered two recent parametrizations for dark energy models: the CBDRM-type and…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-18 Madhur Khurana , Himanshu Chaudhary , Ujjal Debnath , Alok Sardar , G. Mustafa

We explore recent estimations of the Hubble parameter $H$ depending on redshift $z$, which include 31 $H(z)$ data points measured from differential ages of galaxies and 26 data points, obtained with other methods. We describe these data…

General Relativity and Quantum Cosmology · Physics 2018-07-20 G. S. Sharov , V. O. Vasiliev

In this paper, we examine the accelerated expansion of the Universe at late-time in the framework of $f\left( Q\right) $ gravity theory in which the non-metricity scalar $Q$ describes the gravitational interaction. To this, we propose a new…

General Relativity and Quantum Cosmology · Physics 2023-02-21 M. Koussour , S. K. J. Pacif , M. Bennai , P. K. Sahoo

The $H_0$-tension problem poses a confrontation of dark energy driving late-time cosmological expansion measured by the Hubble parameter $H(z)$ over an extended range of redshifts $z$. Distinct values $H_0\simeq 73$ km\,s$^{-1}$Mpc$^{-1}$…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-15 Maurice H. P. M. van Putten

We introduce a holographic dark energy model that incorporates the first-order approximate Kaniadaski entropy, utilizing the Hubble horizon, $1/H$, as the infrared cutoff. We investigate the cosmological evolution within this framework. The…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-14 Wei Fang , Guo Chen , Chao-Jun Feng , Wei Du , Chenggang Shu

Recent measurements of type Ia supernovae as well as other concordant observations suggest that the expansion of our universe is accelerating. A dark energy component has usually been invoked as the most feasible mechanism for the…

Astrophysics · Physics 2014-10-13 Zong-Hong Zhu , Masa-Katsu Fujimoto , Xiang-Tao He

Constraints on the original Cardassian model and the modified polytropic Cardassian model are examined from the latest derived 397 Type Ia supernova (SNe Ia) data, the size of baryonic acoustic oscillation peak from the Sloan Digital Sky…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Tai-Shan Wang , Puxun Wu

By adopting the differential age method, we utilize selected 17832 luminous red galaxies (LRGs) from Sloan Digital Sky Survey Data Release Seven (SDSS DR7) covering redshift $0<z<0.4$ to measure Hubble parameters. Using a full spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-24 Cong Zhang , Han Zhang , Shuo Yuan , Siqi Liu , Tong-Jie Zhang , Yan-Chun Sun

We examine the cosmological implications of measurements of the void-galaxy cross-correlation at redshift $z=0.57$ combined with baryon acoustic oscillation (BAO) data at $0.1<z<2.4$. We find direct evidence of the late-time acceleration…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Seshadri Nadathur , Will J. Percival , Florian Beutler , Hans Winther

In the Cardassian model, dark energy density arises from modifications to the Friedmann equation, which becomes $H^2 = g(\rhom)$, where $g(\rhom)$ is a new function of the energy density. The universe is flat, matter dominated, and…

Astrophysics · Physics 2009-11-07 Yun Wang , Katherine Freese , Paolo Gondolo , Matthew Lewis

As one of the possible extensions of Einstein's General Theory of Relativity, it has been recently suggested that the presence of spacetime torsion could solve problems of the very early and the late-time universe undergoing accelerating…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-19 Tonghua Liu , Ziqiang Liu , Jiamin Wang , Shengnan Gong , Man Li , Shuo Cao

Aiming at exploring the nature of dark energy, we use thirty-six observational Hubble parameter data (OHD) in the redshift range $0 \leqslant z \leqslant 2.36$ to make a cosmological model-independent test of the two-point…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-10 Xiao-Lei Meng , Xin Wang , Shi-Yu Li , Tong-Jie Zhang
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