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Related papers: K-essence Models and Cosmic Acceleration in Genera…

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Observations seem to indicate that our universe is presently accelerating due to the presence of dark energy. Quintessence represents a possible way to model the dark energy. In these proceedings, we briefly review its main properties.

Astrophysics · Physics 2007-05-23 Philippe Brax , Jerome Martin

We apply the teleparallelism condition to the Poincar\'{e} gauge theory of gravity. The resultant teleparallelized cosmology is completely equivalent to the Friedmann cosmology derived from Einstein's general theory of relativity. The…

General Relativity and Quantum Cosmology · Physics 2014-09-10 Wenjie Lu , Wolung Lee , Kin-Wang Ng

We consider a k-essence model in which a single scalar field can be responsible for both primordial inflation and the present observed acceleration of the cosmological background geometry, while also admitting a nonsingular de Sitter…

High Energy Physics - Theory · Physics 2024-01-17 Alexsandre L. Ferreira Junior , Nelson Pinto-Neto , Jorge Zanelli

We present the cosmic expansion scenario in the framework of $f(T)$ gravity by employing a dark energy equation of state (EoS) parameter. Specifically, we proceed with the power-law form of the function $f(T) = \alpha$$(-T)^{n}$, in…

General Relativity and Quantum Cosmology · Physics 2026-04-21 Khomesh R. Patle , G. P. Singh

We discuss a spatially homogeneous and anisotropic Bianchi type-I space-time with two fluids as the content of the Universe: matter and holographic dark energy in the framework of general relativity. To get the exact solutions of Einstein's…

General Relativity and Quantum Cosmology · Physics 2023-02-03 M. Koussour , M. Bennai

$f(Q,T)$ theory of gravity is very recently proposed to incorporate within the action Lagrangian, the trace $T$ of the energy-momentum tensor along with the non-metricity scalar $Q$. The cosmological application of this theory in a…

General Relativity and Quantum Cosmology · Physics 2023-05-24 Tee-How Loo , M. Koussour , Avik De

In the present work, we study the cosmological model with fermionic field and with the non-canonical kinetic term (f-essence). We also present some important reductions of the model as well as its some generalizations. We also found the…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-10 Ratbay Myrzakulov

ecent observations of type Ia supernovae indicate that the Universe is in an accelerating phase of expansion. The fundamental quest in theoretical cosmology is to identify the origin of this phenomenon. In principle there are two…

Astrophysics · Physics 2014-10-13 Marek Szydlowski

We investigate a $(n+1)$-dimensional generalized Randall-Sundrum model with an anisotropic metric which has three different scale factors. One obtain a positive effective cosmological constant $\Omega_{eff}\sim10^{-124}$ (in Planck unit)…

General Relativity and Quantum Cosmology · Physics 2020-12-02 Guang-Zhen Kang , De-Sheng Zhang , Long Du , Dan Shan , Hong-Shi Zong

We present the particular case of the Stephani solution for shear-free perfect fluid with uniform energy density and non-uniform pressure. Such models appeared as possible alternative to the consideration of the exotic forms of matter like…

General Relativity and Quantum Cosmology · Physics 2020-01-22 Elena Kopteva , Irina Bormotova , Maria Churilova , Zdenek Stuchlik

Keeping in mind the current picture of an accelerating and flat Universe, some specific dynamical models of the cosmological term $\Lambda$ have been selected for investigating the nature of dark energy. Connecting the free parameters of…

Astrophysics · Physics 2008-11-26 Saibal Ray , Utpal Mukhopadhyay , Xin-He Meng

Understanding the accelerating expansion of the Universe remains a fundamental challenge in modern cosmology. In this paper, we investigate a cosmological model parametrized by a generalized variable deceleration parameter to elucidate the…

General Relativity and Quantum Cosmology · Physics 2023-09-29 M. Koussour , N. Myrzakulov , Alnadhief H. A. Alfedeel , F. Awad , M. Bennai

In this study, cosmological models with perfect fluid and a gravitational framework f(Q) will be examined. In this modified theory of gravity, the gravitational force has the form f(Q), where Q stands for the non-metricity scalar. I create…

General Relativity and Quantum Cosmology · Physics 2022-08-08 A. Y. Shaikh

The accelerated expansion of the universe remains one of the most profound puzzles in modern cosmology, often attributed to dark energy within the framework of General Relativity. As an alternative, modified teleparallel gravity theories…

General Relativity and Quantum Cosmology · Physics 2025-12-23 K. S. Kavya , T. Vinutha , B. Revathi

We explicitly construct the k-essence models which reproduce the arbitrary FRW cosmology, that is, the arbitrary time-development of the scale factor or the Hubble rate. The k-essence model includes scalar quintessence model, tachyon dark…

High Energy Physics - Theory · Physics 2010-04-30 Jiro Matsumoto , Shin'ichi Nojiri

One possible explanation for the present observed acceleration of the Universe is the breakdown of homogeneity and isotropy due to the formation of non-linear structures. How inhomogeneities affect the averaged cosmological expansion rate…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Jose Beltran Jimenez , Alvaro de la Cruz-Dombriz , Peter K. S. Dunsby , Diego Saez-Gomez

We investigate the physical properties of a purely kinetic k-essence model with an equation of state motivated in superconducting membranes. We compute the equation of state parameter $w$ and discuss its physical evolution via a nonlinear…

General Relativity and Quantum Cosmology · Physics 2017-08-02 Ruben Cordero , Eduardo L. Gonzalez , Alfonso Queijeiro

The primary aim of this work is to explore feasible bouncing cosmological solutions in the framework of $f(\mathcal{Q}, \mathcal{C})$ gravity, where $\mathcal{Q}$ denotes non-metricity and $\mathcal{C}$ indicates the boundary term. To…

General Relativity and Quantum Cosmology · Physics 2025-08-12 M. Sharif , M. Zeeshan Gul , Ahmad Nawaz

Some new exact solutions of Einstein's field equations in a spatially homogeneous and anisotropic Bianchi type-V space-time with minimally interaction of perfect fluid and dark energy components have been obtained. To prevail the…

General Physics · Physics 2011-10-06 Anirudh Pradhan , H. Amirhashchi

We obtain lagrangian for $k$-essence scalar field $\phi(r,t)$ with scalar curvature $k$ of Friedmann-Lemaitre-Robertson-Walker (FLRW) metric . Obtained lagrangian has two generalised co-ordinates $\phi$ and logarithm of scale factor ($q=\ln…

General Physics · Physics 2020-06-12 Somnath Mukherjee
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