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Related papers: Phantom evolution in power-law potentials

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The hypothesis is rapidly gaining popularity that the dark energy pervading our universe is extra-repulsive ($-p>\rho$). The density of such a substance(usually called phantom energy) grows with the cosmological expansion and may become…

Astrophysics · Physics 2010-02-01 Anton Baushev

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…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-21 Carlos García-García , Eric V. Linder , Pilar Ruíz-Lapuente , Miguel Zumalacárregui

Quintessence is a canonical scalar field introduced to explain the late-time cosmic acceleration. The cosmological dynamics of quintessence is reviewed, paying particular attention to the evolution of the dark energy equation of state w.…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Shinji Tsujikawa

The recent observations support that our universe is flat and expanding with acceleration. A quintessence model with a general relation between the quintessence potential and the quintessence kinetic energy was proposed to explain the…

Astrophysics · Physics 2009-11-10 Yungui Gong

We extend the dynamical systems analysis of Scalar-Fluid interacting dark energy models performed in C. G. Boehmer et al, Phys. Rev. D 91, 123002 (2015), by considering scalar field potentials beyond the exponential type. The properties and…

General Relativity and Quantum Cosmology · Physics 2017-02-01 Jibitesh Dutta , Wompherdeiki Khyllep , Nicola Tamanini

We describe a method to derive the expansion and acceleration rates directly from the data, without the need for the specification of a theory of gravity, and without adopting an a priori parameterization of the form or redshift evolution…

Astrophysics · Physics 2007-05-23 Ruth A. Daly , S. G. Djorgovski

Dark energy away from a cosmological constant $\Lambda$ -- like early universe inflation that ends -- can be understood in terms of well defined physical behaviors. These guide dark energy into thawing or freezing classes, with $w_0$--$w_a$…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-16 Eric V. Linder

We show the effectiveness of using the procedure of the potential reconstruction (the V-method) in the estimation of the transition redshift corresponding to switch from deceleration to acceleration phase of the Universe. We investigate the…

Astrophysics · Physics 2007-05-23 Wojciech Czaja , Marek Szydlowski , Adam Krawiec

Power-law solutions for $f(G)$ gravity coupled with perfect fluid have been studied for spatially flat universe. It is shown that despite the matter dominated and accelerating power-law solutions, the power-law solution exists for an…

General Relativity and Quantum Cosmology · Physics 2012-02-09 A. R. Rastkar , M. R. Setare , F. Darabi

We survey the application of specific tools to distinguish amongst the wide variety of dark energy models that are nowadays under investigation. The first class of tools is more mathematical in character: the application of the theory of…

General Relativity and Quantum Cosmology · Physics 2009-12-05 Genly Leon , Yoelsy Leyva , Emmanuel N. Saridakis , Osmel Martin , Rolando Cardenas

This article explores the cosmological scenario of the universe in the context of the $f(T)$ power law model, where $T$ represent the torsion scalar. To obtain the deterministic solution of the field equations we parametrized the effective…

General Relativity and Quantum Cosmology · Physics 2024-11-11 S. R. Bhoyar , Yash B. Ingole

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

Friedmann-Robertson-Walker universes with a presently large fraction of the energy density stored in an $X$-component with $w_X<-1/3$, are considered. We find all the critical points of the system for constant equations of state in that…

General Relativity and Quantum Cosmology · Physics 2011-05-05 M. Chevallier , D. Polarski

A generalized quintessence model is presented which corresponds to a richer vacuum structure that, besides a time-dependent, slowly varying scalar field, contains a varying cosmological term. From first principles we determine a number of…

Astrophysics · Physics 2009-10-31 Pedro F. Gonzalez-Diaz

We apply a new non-parametric Bayesian method for reconstructing the evolution history of the equation-of-state $w$ of dark energy, based on applying a correlated prior for $w(z)$, to a collection of cosmological data. We combine the latest…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-20 Gong-Bo Zhao , Robert G. Crittenden , Levon Pogosian , Xinmin Zhang

Consistency relations between growth of structure and expansion history observables exist for any physical explanation of cosmic acceleration, be it a cosmological constant, scalar field quintessence, or a general component of dark energy…

Astrophysics · Physics 2010-04-15 Michael J. Mortonson , Wayne Hu , Dragan Huterer

Using a correspondence between the f(T)-gravity with the power-law entropy corrected version of the holographic dark energy model, we reconstruct the holographic f(T)-gravity model with power-law entropy correction. We fit the model…

General Relativity and Quantum Cosmology · Physics 2013-11-06 K. Karami , S. Asadzadeh , A. Abdolmaleki , Z. Safari

We explore freezing dark energy, where the evolution of the field approaches that of a cosmological constant at late times. We propose two general, two parameter forms to describe the class of freezing field models, in analogy to ones for…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-22 Eric V. Linder

Recently, attempts have been made to understand the apparent near coincidence of the present dark energy and matter energy in terms of a dynamical attractor-like solution for the evolution of a scalar field. In these models the field…

Astrophysics · Physics 2009-11-06 M. Yahiro , G. J. Mathews , K. Ichiki , T. Kajino , M. Orito

Evolution of a background space-time metric and sub-horizon matter density perturbations in the Universe is numerically analyzed in viable $f(R)$ models of present dark energy and cosmic acceleration. It is found that viable models…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-10 Hayato Motohashi , Alexei A. Starobinsky , Jun'ichi Yokoyama
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