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Related papers: Power law cosmology - a viable alternative

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"Power Law Cosmologies" are defined by their growth of the cosmological scale factor as $ t^\alpha$ regardless of the matter content or cosmological epoch. Constraints from the current age of the Universe and from the high redshift…

Astrophysics · Physics 2007-05-23 Sethi Meetu , Batra Annu , Lohiya Daksh

In a class of models designed to solve the cosmological constant problem by coupling scalar or tensor classical fields to the space-time curvature, the universal scale factor grows as a power law in the age, $a \propto t^\alpha$, regardless…

Astrophysics · Physics 2016-08-25 M. Kaplinghat , G. Steigman , I. Tkachev , T. P. Walker

Power-law cosmology with scale factor as power of cosmic time, $a \propto t^{\a}$, is investigated. We review and discuss value of $\a$ obtained from various types of observation. Considering dark energy dominant era in late universe from…

Cosmology and Nongalactic Astrophysics · Physics 2013-08-30 Burin Gumjudpai

We revise observational constraints on the class of models of modified gravity which at low redshifts lead to a power-law cosmology. To this end we use available public data on Supernova Ia and on baryon acoustic oscillations. We show that…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 A. Dolgov , V. Halenka , I. Tkachev

Not much by themselves, aparently. We try to reconstruct the scale factor $a(t)$ of the universe from the SNe Ia data, i.e. the luminosity distance $d_{L}(z)$, using only the cosmological principle and the assumption that gravitation is…

General Relativity and Quantum Cosmology · Physics 2017-06-19 İbrahim Semiz , A. Kazım Çamlıbel

We consider a late closed universe of which scale factor is a power function of time using observational data from combined WMAP5+BAO+SNIa dataset and WMAP5 dataset. The WMAP5 data give power-law exponent, $\alpha = 1.01$ agreeing with the…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-30 Burin Gumjudpai , Kiattisak Thepsuriya

In this paper, we show that the expansion history of the Universe in power-law cosmology essentially depends on two crucial parameters, namely the Hubble constant $H_{0}$ and deceleration parameter $q$. We find the constraints on these…

General Relativity and Quantum Cosmology · Physics 2014-08-27 Suresh Kumar

A strictly linear evolution of the cosmological expansion scale factor is a characteristic feature in several classes of alternative gravity theories as also in the standard (big-bang) model with specially chosen equations of state of…

Astrophysics · Physics 2009-10-31 Abha Dev , Meetu Sethi , Daksh Lohiya

We derive a model of dark energy which evolves with time via the scale factor. The equation of state $\omega=(1-2\alpha)/(1+2\alpha)$ is studied as a function of a parameter $\alpha$ introduced in this model. In addition to the recent…

General Relativity and Quantum Cosmology · Physics 2017-06-20 Hemza Azri , A. Bounames

We perform a model independent reconstruction of the cosmic expansion rate based on type Ia supernova data. Using the Union 2.1 data set, we show that the Hubble parameter behaviour allowed by the data without making any hypothesis about…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 S. Benitez-Herrera , E. E. O. Ishida , M. Maturi , W. Hillebrandt , M. Bartelmann , F. Röpke , .

We present new observational constraints on Lorentz violating Ho\v{r}ava-Lifshitz cosmological scenarios using an updated cosmological data set from Cosmic Microwave Background (Planck CMB), expansion rates of elliptical and lenticular…

General Relativity and Quantum Cosmology · Physics 2018-12-31 Nils A. Nilsson , Ewa Czuchry

We investigate observational constraints on the curvature of the universe not restricting ourselves to a cosmological constant as dark energy, in particular allowing a dark energy equation of state to evolve with time in several ways. We…

Astrophysics · Physics 2010-10-27 Kazuhide Ichikawa , Tomo Takahashi

In this paper, we examine observational constraints on the power law cosmology; essentially dependent on two parameters $H_0$ (Hubble constant) and $q$ (deceleration parameter). We investigate the constraints on these parameters using the…

General Relativity and Quantum Cosmology · Physics 2015-03-20 Sarita Rani , A. Altaibayeva , M. Shahalam , J. K. Singh , R. Myrzakulov

Applying the distance sum rule in strong gravitational lensing (SGL) and type Ia supernova (SN Ia) observations, one can provide an interesting cosmological model-independent method to determine the cosmic curvature parameter $\Omega_k$. In…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-31 Bo Wang , Jing-Zhao Qi , Jing-Fei Zhang , Xin Zhang

We constrain two non-flat time-evolving dark energy cosmological models by using Hubble parameter data, Type Ia supernova apparent magnitude measurements, and baryonic acoustic oscillation peak length scale observations. The inclusion of…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Omer Farooq , Data Mania , Bharat Ratra

The energy density of a scalar field $\phi$ with potential $V(\phi) \propto \phi^{-\alpha}$, $\alpha > 0$, behaves like a time-variable cosmological constant that could contribute significantly to the present energy density. Predictions of…

Astrophysics · Physics 2009-10-31 Silviu Podariu , Bharat Ratra

We use the statistics of strong gravitational lensing based on the Cosmic Lens All-Sky Survey (CLASS) data to constrain cosmological parameters in a spatially-flat, inverse power-law potential energy density, scalar-field dark energy…

Astrophysics · Physics 2009-11-10 Kyu-Hyun Chae , Gang Chen , Bharat Ratra , Dong-Wook Lee

The free parameters of a flat accelerating model without dark energy are constrained by using Supernovae type Ia and observational H(z) data. Instead of the vacuum dominance, the present accelerating stage in this modified Einstein-de…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-15 R. C. Santos , F. E. Silva , J. A. S. Lima

In this study, we present an approach $ f(R, G) $ gravity incorporating power law in $ G $. To study the cosmic evolution of the universe given by the reconstruction of the Hubble parameter given by $ E(z) = \bigg(…

General Relativity and Quantum Cosmology · Physics 2024-09-30 Rita Rani , Shaily , G. K. Goswami , J. K. Singh

This paper examines a cosmological model of scale-dependent gravity. The gravitational action is taken to be the Einstein-Hilbert term supplemented with a cosmological constant, where the couplings, $G_k$ and $\Lambda_k$, run with the…

General Relativity and Quantum Cosmology · Physics 2024-05-29 Pedro D. Alvarez , Benjamin Koch , Cristobal Laporte , Angel Rincon
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