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Related papers: Some exact solutions in K-essence theory isotropic…

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The paper deals with cosmological solutions describing different phases of the Universe for the homogeneous and isotropic FLRW model of the Universe with torsion. Normally, torsion field is not suitable for maximally symmetric space time…

General Relativity and Quantum Cosmology · Physics 2020-10-30 Akash Bose , Subenoy Chakraborty

We explore the possibility that a scalar field with appropriate Lagrangian can mimic a perfect fluid with an affine barotropic equation of state. The latter can be thought of as a generic cosmological dark component evolving as an effective…

Astrophysics · Physics 2008-11-26 Claudia Quercellini , Marco Bruni , Amedeo Balbi

We consider a connection between the holographic dark energy density and the kinetic k-essence energy density in a flat FRW universe. With the choice $c\geq1$, the holographic dark energy can be described by a kinetic k-essence scalar field…

General Relativity and Quantum Cosmology · Physics 2009-09-28 Norman Cruz , Pedro F. Gonzalez-Diaz , Alberto Rozas-Fernandez , Guillermo Sanchez

A cosmological model with perfect fluid and self-interacting quintessence field is considered in the framework of the spatially flat Friedmann-Robertson-Walker (FRW) geometry. By assuming that all physical quantities depend on the volume…

General Relativity and Quantum Cosmology · Physics 2009-11-07 M. K. Mak , T. Harko

K-essence models, relying on scalar fields with non-canonical kinetic terms, have been proposed as an alternative to quintessence in explaining the observed acceleration of the Universe. We consider the use of field redefinitions to cast…

Astrophysics · Physics 2011-06-21 Michael Malquarti , Edmund J Copeland , Andrew R Liddle , Mark Trodden

Using a particular form of the quantum K-essence scalar field, we show that in the quantum formalism, a fractional differential equation in the scalar field variable, for some epochs in the Friedmann-Lema\^itre-Robertson-Walker (FLRW) model…

General Relativity and Quantum Cosmology · Physics 2023-04-14 J. Socorro , J. Juan Rosales

A general approach to find out exact cosmological solutions in f(R)-gravity is discussed. Instead of taking into account phenomenological models, we assume, as a physical criterium, the existence of Noether symmetries in the cosmological…

General Relativity and Quantum Cosmology · Physics 2010-02-10 Salvatore Capozziello , Antonio De Felice

We study the $f(R,T)$ cosmological models under the self-similarity hypothesis. We determine the exact form that each physical and geometrical quantity may take in order that the Field Equations (FE) admit exact self-similar solutions…

Cosmology and Nongalactic Astrophysics · Physics 2022-09-02 José Antonio Belinchón , Carlos González , Sami Dib

This paper reviews the dynamics of an isotropic and homogeneous cosmological scalar field. A general approach to the solution of the Einstein-Klein-Gordon equations is developed, which does not require slow-roll or other approximations.…

General Relativity and Quantum Cosmology · Physics 2025-04-15 J. W. van Holten

We present new exact inhomogeneous vacuum cosmological solutions of Einstein's equations. They provide new information about the nature of general cosmological solutions to Einstein's equations.

General Relativity and Quantum Cosmology · Physics 2007-05-23 John D. Barrow , Kerstin E. Kunze

The anisotropic Bianchi type I in multi-scalar field cosmology is studied with a particular potential of the form $\rm V= V_0 e^{-\left[\lambda_1 \phi_1 + \cdots + \lambda_n \phi_n \right]}\,,$ which emerges as a condition between the time…

General Relativity and Quantum Cosmology · Physics 2019-04-02 j. Socorro , Omar E. Núñez , Rafael Hernández-Jiménez

Using technique of supersymmetric quantum mechanics we present new cosmological quantum solution, in the regime for FRW cosmological model using a barotropic perfect fluid as matter field.

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. Socorro

We investigate a Bianchi type-I (BTI) cosmology with k essence and find the set of models which dissipate the initial anisotropy. There are cosmological models with extended tachyon fields and k essence having constant bariotropic index. We…

Astrophysics · Physics 2009-11-13 Luis P. Chimento , Mónica Forte

We derive a condition for converging a common evolutionary track for k-essence (a scalar field dark energy with non-canonical kinetic terms). For the Lagrangian density V(phi)W(X) with X=dot{phi}^2/2, we find tracker solutions with w_{phi}…

Astrophysics · Physics 2009-11-07 Takeshi Chiba

We calculate the cosmological complexity under the framework of scalar curvature perturbations for a K-essence model with constant potential. In particular, the squeezed quantum states are defined by acting a two-mode squeezed operator…

General Relativity and Quantum Cosmology · Physics 2021-02-26 Ai-chen Li , Xin-Fei Li , Ding-fang Zeng , Lei-Hua Liu

In this paper, we perform a dynamical systems study of the purely kinetic k-essence. Although these models have been studied in the past, a full study of the dynamics in the phase space incorporating the stability conditions for theoretical…

General Relativity and Quantum Cosmology · Physics 2025-02-11 Israel Quiros , Tame Gonzalez , Ulises Nucamendi , Roberto De Arcia , Francisco Antonio Horta Rangel

Multidimensional cosmological model describing the evolution of a fluid with shear and bulk viscosity in $n$ Ricci-flat spaces is investigated. The barotropic equation of state for the density and the pressure in each space is assumed. The…

General Relativity and Quantum Cosmology · Physics 2010-04-30 V. R. Gavrilov , V. N. Melnikov , Roland Triay

The Wheeler-DeWitt equation is solved for some scalar-tensor theories of gravitation in the case of homogeneous and isotropic cosmological models.We present general solutions corresponding to cosmological term: (i)\lambda(\phi)=0$ and $(ii)…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Luis O. Pimentel , César Mora

We report on the cited papers refs. 1 - 18 from the following points of view: What do we exactly know about solutions when no exact solution (in the sense of "solution in closed form") is available? In which sense do these solutions possess…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. -J. Schmidt

We solve isotropic, homogeneous cosmological models containing a self-interacting scalar field. Calculations are performed in four and two-dimensional spacetimes. We find several exact solutions that have an inflationary regime or has a…

General Relativity and Quantum Cosmology · Physics 2012-08-07 Luis P. Chimento , Adriana E. Cossarini , Alejandro S. Jakubi