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Related papers: Observational constraints on Modified Chaplygin Ga…

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Early dark energy models, for which the contribution to the dark energy density at high redshifts is not negligible, influence the growth of cosmic structures and could leave observable signatures that are different from the standard…

Cosmology and Nongalactic Astrophysics · Physics 2009-04-01 Jun-Qing Xia , Matteo Viel

The expansion rate of the Universe changes with time, initially slowing (decelerating) when the universe was matter dominated, because of the mutual gravitational attraction of all the matter in it, and more recently speeding up…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-17 Muhammad Omer Farooq

Any Dark Energy (DE) or Modified Gravity (MG) model that deviates from a cosmological constant requires a consistent treatment of its perturbations, which can be described in terms of an effective entropy perturbation and an anisotropic…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-26 Bjoern Soergel , Tommaso Giannantonio , Jochen Weller , Richard A. Battye

An exotic dark component, named generalized Chaplygin gas (Cg) and parameterized by an equation of state $p = -A/\rho_{Cg}^{\alpha}$ where $A$ and $\alpha$ are arbitrary constants, is one of the possible candidates for dark energy as well…

Astrophysics · Physics 2009-11-10 J. S. Alcaniz , J. A. S. Lima

The cosmic curvature density parameter has been constrained in the present work independent of any background cosmological model. The reconstruction is performed adopting the non-parametric Gaussian Processes (GP). The constraints on…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-18 Purba Mukherjee , Narayan Banerjee

We investigate the constraints on cosmological parameters especially for EoS of dark energy, inflationary parameters, neutrino mass and curvature of universe using simulated Planck data. Firstly we determine cosmological parameters with…

Astrophysics · Physics 2014-11-18 Jun-Qing Xia , Hong Li , Gong-Bo Zhao , Xinmin Zhang

The generalized Chaplygin gas model with parameter space $\alpha>-1$ is studied in this paper. Some reasonable physical constraints are added to justify the use of the larger parameter space. The Type Ia supernova data and age data of some…

Astrophysics · Physics 2008-11-26 Yungui Gong

In this paper, observational constraints on the cosmic equation of state of dark energy ($p = w \rho$) have been investigated using gravitational lensing statistics. A likelihood analysis of the lens surveys has been carried out to…

Astrophysics · Physics 2009-09-25 Abha Dev , Deepak Jain , N. Panchapakesan , S. Mahajan , V. B. Bhatia

We use measurements from the Planck satellite mission and galaxy redshift surveys over the last decade to test three of the basic assumptions of the standard model of cosmology, $\Lambda$CDM: the spatial curvature of the universe, the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-20 Shadab Alam , Shirley Ho , Alessandra Silvestri

In order to explain the current acceleration of the Universe, the fine tuning problem of the cosmological constant $\Lambda$ and the cosmic coincidence problem, different alternative models have been proposed in the literature. We use the…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-13 Alexander Bonilla Rivera , Jorge García Farieta

We study how the cosmological constraints from growth data are improved by including the measurements of bias from Dark Energy Survey (DES). In particular, we utilize the biasing properties of the DES Luminous Red Galaxies (LRGs) and the…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-22 Spyros Basilakos , Fotios K. Anagnostopoulos

Under the commonly used assumption that clumped objects can be well described by a spherical top-hat matter density profile, we investigate the evolution of the cosmic growth index in clustering dark energy (CDE) scenarios on sub-horizon…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-06 Ahmad Mehrabi , Mohammad Malekjani , Francesco Pace

We present constraints on the cosmic growth history with recent cosmological data, allowing for deviations from Lambda CDM as might arise if cosmic acceleration is due to modifications to GR or inhomogeneous dark energy. We combine measures…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-12 Rachel Bean , Matipon Tangmatitham

The cosmological model of the modified Chaplygin gas interacting with cold dark matter is studied. Our attention is focused on the final state of universe in the model. It turns out that there exists a stable scaling solution, which…

General Relativity and Quantum Cosmology · Physics 2009-12-04 Song Li , Yongge Ma , Yun Chen

We studied the cosmological constraints on the Galileon gravity obtained from observational data of the growth rate of matter density perturbations, the supernovae Ia (SN Ia), the cosmic microwave background (CMB), and baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-03 Koichi Hirano , Zen Komiya , Hisato Shirai

We investigate the unification scenario provided by the generalised Chaplygin gas model (a perfect fluid characterized by an equation of state p = -A/\rho^{\alpha}). Our concerns lie with a possible tension existing between background…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-18 Juliano Pereira Campos , Júlio César Fabris , Rafael Perez , Oliver F. Piattella , Hermano Velten

Although various cosmological observations congruously suggest that our universe is dominated by two dark components, the cold dark matter without pressure and the dark energy with negative pressure, the nature and origin of these…

Astrophysics · Physics 2009-11-10 Zong-Hong Zhu

The type Ia supernovae observational data are used to estimate the parameters of a cosmological model with cold dark matter and the Chaplygin gas. The Chaplygin gas model depends essentially on four parameters: the Hubble constant, the…

Astrophysics · Physics 2009-12-30 R. Colistete , J. C. Fabris , S. V. B. Gonçalves , P. E. de Souza

We use higher-redshift gamma-ray burst (GRB), HII starburst galaxy (HIIG), and quasar angular size (QSO-AS) measurements to constrain six spatially flat and non-flat cosmological models. These three sets of cosmological constraints are…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Shulei Cao , Joseph Ryan , Narayan Khadka , Bharat Ratra

We present limits on the parameters of the o$\Lambda$CDM, $w_0$CDM, and $w_0 w_a$CDM models obtained from the joint analysis of the full-shape, baryon acoustic oscillations (BAO), big bang nucleosynthesis (BBN) and supernovae data. Our…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-16 Anton Chudaykin , Konstantin Dolgikh , Mikhail M. Ivanov
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