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Related papers: Interacting dark energy: generic cosmological evol…

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Motivated by the recent interest in cosmologies arising from energy density modifications to the Friedmann equation, we analyse the scaling behaviour for a broad class of these cosmologies comprised of scalar fields and background…

Astrophysics · Physics 2009-11-10 Edmund J. Copeland , Seung-Joo Lee , James E. Lidsey , Shuntaro Mizuno

This paper consider an universe dominated by baryonic matter, radiation and a nonminimally coupled massive scalar field under the action of a symmetry breaking potential. Inflation occurs naturally with appropriated slow-roll values. The…

Cosmology and Nongalactic Astrophysics · Physics 2021-11-02 S. H. Pereira

We discuss the coupling between dark energy and matter by considering a homogeneous tachyonic scalar field as a candidate for dark energy. We obtained the functional form of scale factor by assuming that the coupling strength depends…

General Relativity and Quantum Cosmology · Physics 2021-01-27 A Kundu , S D Pathak , V K Ojha

In this talk, I have discussed the implications of a multi-component nature of cosmic Dark Matter for the observational bounds on possible long-range fifth-forces mediated by a Dark Energy scalar field. By assuming a simple internal…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-19 Marco Baldi

Phantom energy can be visualized as a scalar field with a (non-canonical) negative kinetic energy term. We use the dynamical system formalism to study the attractor behavior of a cosmological model containing a phantom scalar field $\phi$…

Astrophysics · Physics 2009-11-13 L. Arturo Urena-Lopez

We give a scalar field description of two dark energy parameterizations, and we analyze in detail its cosmology both at the level of background evolution and at the level of linear perturbations. In particular, we compute the statefinder…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-02 G. Panotopoulos

In this paper, we investigate a non-canonical scalar field model in the background dynamics of anisotropic Locally Rotationally Symmetric (LRS) Bianchi type I universe where gravity is coupled minimally to scalar field which is taken as…

General Relativity and Quantum Cosmology · Physics 2023-11-17 Sujoy Bhanja , Goutam Mandal , Abdulla Al Mamon , Sujay Kr. Biswas

In this letter we study a model of interaction between the scalar field and an inhomogeneous ideal fluid. We have considered two forms of the ideal fluid and a power law expansion for the scale factor. We have solved the equations for the…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Writambhara Chakraborty , Ujjal Debnath

Cosmological scaling solutions, which give rise to a scalar-field density proportional to a background fluid density during radiation and matter eras, are attractive to alleviate the energy scale problem of dark energy. In the presence of…

General Relativity and Quantum Cosmology · Physics 2010-03-25 Junko Ohashi , Shinji Tsujikawa

We study the cosmological dynamics of dark energy in a scalar-vector-torsion theory. The vector field is described by the cosmic triad and the scalar field is of the quintessence type with non-minimal coupling to gravity. The coupling to…

General Relativity and Quantum Cosmology · Physics 2023-07-11 Manuel Gonzalez-Espinoza , Giovanni Otalora , Yoelsy Leyva , Joel Saavedra

We consider a scalar-tensor theory in teleparallel gravity where a general function of the scalar field, f(phi), is non-minimally coupled to the torsion scalar T. First, we derive the field equations in this framework. Then, we study the…

General Relativity and Quantum Cosmology · Physics 2025-07-15 Naser Mohammadipour

Non-gravitational interaction between two barotropic dark fluids, namely the pressureless dust and the dark energy in a spatially flat Friedmann-Lema\^{i}tre-Robertson-Walker model has been discussed. It is shown that for the interactions…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-30 Supriya Pan , Ankan Mukherjee , Narayan Banerjee

This paper aims to introduce a new parameterisation for the coupling Q in interacting dark matter and dark energy models by connecting said models with the Continuous Tower of Scalar Fields model. Based upon the existence of a dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 Paulo Santos

The present work is an example of the application of the dynamical system analysis in the context of cosmology. Here cosmic evolution is considered in the background of homogeneous and isotropic flat Friedmann-Lema\^{i}tre-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2020-11-20 Soumya Chakraborty , Sudip Mishra , Subenoy Chakraborty

We study the cosmology of a general scalar field and barotropic fluid during the early stage of a brane-world where the Friedmann constraint is dominated by the square of the energy density. Assuming both the scalar field and fluid are…

Astrophysics · Physics 2009-11-10 Shuntaro Mizuno , Seung-Joo Lee , Edmund J. Copeland

We propose a new Dark Energy parametrization based on the dynamics of a scalar field. We use an equation of state $w=(x-1)/(x+1)$, with $x=E_k/V$, the ratio of kinetic energy $E_k=\dot\phi^2/2$ and potential $V$. The eq. of motion gives…

Cosmology and Nongalactic Astrophysics · Physics 2011-12-09 Axel de la Macorra

This paper presents an investigation of cosmological dynamics of tachyon fluid coupled to varyingmass dark matter particles in the background of spatially flat FLRW universe. The mechanism of varying mass particles scenario assumes the mass…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Goutam Mandal , Sudip Mishra , Abdulla Al Mamon , Sujay Kr. Biswas

We study cosmological dynamics of an extended gravitational theory that gravity is coupled non-minimally with derivatives of a dark energy component and there is also a phenomenological interaction between the dark energy and dark matter.…

General Relativity and Quantum Cosmology · Physics 2016-05-20 Kourosh Nozari , Noushin Behrouz

The present work deals with an interacting dark energy model in the framework of f(T) cosmology. A cosmologically viable form of f(T) is chosen (T is the torsion scalar in teleparallelism) in the background of flat homogeneous and isotropic…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Sujay Kr. Biswas , Subenoy Chakraborty

We analyze the dynamical system defined by a universe filled with a barotropic fluid plus a scalar field with modified kinetic term of the form L = F (X) - V (phi). After a suitable choice of variables that allows us to study the phase…

General Relativity and Quantum Cosmology · Physics 2015-03-20 Josue De-Santiago , Jorge L. Cervantes-Cota , David Wands
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