English
Related papers

Related papers: Observational constraints on phantom power-law cos…

200 papers

We constrain the scalar field dark energy model with an inverse power-law potential, i.e., $V(\phi)\propto {\phi}^{-\alpha}$ ($\alpha>0$), from a set of recent cosmological observations by compiling an updated sample of Hubble parameter…

Cosmology and Nongalactic Astrophysics · Physics 2015-02-10 Yun Chen , Chao-Qiang Geng , Shuo Cao , Yu-Mei Huang , Zong-Hong Zhu

An overview is presented of a recently proposed "radically conservative" solution to the problem of dark energy in cosmology. The proposal yields a model universe which appears to be quantitatively viable, in terms of its fit to supernovae…

Astrophysics · Physics 2017-08-23 David L. Wiltshire

We introduce a power-law parameterized quintessence model for the dark energy which accelerate universe at the low redshifts while behaves as an ordinary matter for the early universe. We construct a unique scalar potential for this…

Astrophysics · Physics 2008-11-26 Sohrab Rahvar , M. Sadegh Movahed

Lensing peaks have been proposed as a useful statistic, containing cosmological information from non-Gaussianities that is inaccessible from traditional two-point statistics such as the power spectrum or two-point correlation functions.…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-05 Jia Liu , Andrea Petri , Zoltan Haiman , Lam Hui , Jan M. Kratochvil , Morgan May

Measurements of large-scale structure are interpreted using theoretical predictions for the matter distribution, including potential impacts of baryonic physics. We constrain the feedback strength of baryons jointly with cosmology using…

We investigate a dynamical reconstruction of the dark energy equation of state parameter by assuming that it satisfies a law of motion described by an autonomous second-order differential equation, with the limit of the cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-25 Andronikos Paliathanasis

We present a new model for the full shape of large-scale the power spectrum based on renormalized perturbation theory. To test the validity of this prescription, we compare this model against power spectra measured in a suite of 50 large…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-03 Francesco Montesano , Ariel G. Sanchez , Stefanie Phleps

A parametric reconstruction of the jerk parameter, the third order derivative of the scale factor expressed in a dimensionless way, has been discussed. Observational constraints on the model parameters have been obtained by Maximum…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Ankan Mukherjee , Narayan Banerjee

Dark energy with the usually used equation of state $p=w\rho$, where $w=const<0$ is hydrodynamically unstable. To overcome this drawback we consider the cosmology of a perfect fluid with a linear equation of state of a more general form…

Astrophysics · Physics 2009-11-06 E. Babichev , V. Dokuchaev , Yu. Eroshenko

We present the newest statistical and numerical analysis of the matter and cosmic microwave background power spectrum with effects of the primordial magnetic field (PMF) included. New limits to the PMF strength and power spectral index are…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Dai G. Yamazaki , Kiyotomo Ichiki , Toshitaka Kajino , Grant. J. Mathews

We constrain plausible dark energy models, parametrized by multiple candidate equation of state, using the recently published Cosmic Microwave Background (CMB) temperature anisotropy data from Planck together with the WMAP-9 low-$\ell$…

Cosmology and Nongalactic Astrophysics · Physics 2015-04-22 Dhiraj Kumar Hazra , Subhabrata Majumdar , Supratik Pal , Sudhakar Panda , Anjan A. Sen

Using an approximate likelihood method adapted to band--power estimates, we analyze the ensemble of first generation cosmic microwave background anisotropy experiments to deduce constraints over a six--dimensional parameter space describing…

Astrophysics · Physics 2011-05-23 M. Le Dour , M. Douspis , J. G. Bartlett , A. Blanchard

Dark energy of phantom or quintessence nature with an equation of state parameter $w$ almost equal to -1 often leads the universe evolution to a finite-time future singularity. An elegant solution to this problem has been recently proposed…

High Energy Physics - Theory · Physics 2013-05-29 I. Brevik , E. Elizalde , S. Nojiri , S. D. Odintsov

With due consideration of reasonable cosmological assumptions within the limit of the present cosmological scenario, we have analysed a spherically symmetric metric in 5D setting within the framework of Lyra manifold. The model universe is…

General Relativity and Quantum Cosmology · Physics 2020-11-25 Pheiroijam Suranjoy Singh , Kangujam Priyokumar Singh

Friedmans cosmological equations for the scale factor are analyzed for the Universe containing dark energy. The parameter of the equation of state of the dark energy is treated as an arbitrary constant whose value lies within the interval…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-13 M. V. Sazhin , O. S. Sazhina , U. Chadayammuri

The high-energy non-thermal universe is dominated by power law-like spectra. Therefore results in high-energy astronomy are often reported as parameters of power law fits, or, in the case of a non-detection, as an upper limit assuming the…

Instrumentation and Methods for Astrophysics · Physics 2017-02-23 Max L. Ahnen

The measurement of the scale of the baryon acoustic oscillations (BAO) in the galaxy power spectrum as a function of redshift is a promising method to constrain the equation-of-state parameter of the dark energy w. To measure the scale of…

Astrophysics · Physics 2009-06-23 Christian Wagner , Volker Müller , Matthias Steinmetz

It is well-known that even high quality cosmic microwave background (CMB) observations are not sufficient on their own to determine the equation of state of the dark energy, due to the effect of the so-called geometric degeneracy at large…

The cosmic acceleration observed in the expansion of the Universe has sparked extensive research into the nature of dark energy, which is known to constitute approximately 70\% of the Universe's energy content. In this study, we explore two…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-26 M. Koussour , N. S. Kavya , V. Venkatesha , N. Myrzakulov

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
‹ Prev 1 3 4 5 6 7 10 Next ›