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We study FRW cosmology for a double scalar - tensor theory of gravity where two scalar fields are nonminimally coupled to the geometry. In a framework to study stability and attractor solutions of the model in the phase space, we constraint…

General Physics · Physics 2015-06-03 H. Farajollahi , A. Shahabi , A. Salehi

We consider the spatially flat Friedmann-Lemaitre-Robertson-Walker space time in the teleparallel model of gravity and assume that the universe is filled nearly by cold dark matter and a nonminimally coupled scalar field with a power-law…

General Relativity and Quantum Cosmology · Physics 2017-04-11 H. Mohseni Sadjadi

We propose a model of dark energy consists of a single scalar field with a general non-minimal kinetic couplings to itself and to the curvature. We study the cosmological dynamics of the equation of state in this setup. The coupling terms…

General Physics · Physics 2015-06-05 A. Banijamali , B. Fazlpour

We study dynamics of the equation of state parameter for a dark energy component non-minimally coupled to induced gravity on a warped DGP brane. We show that there are appropriate domains of the model parameters space that account for…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Kourosh Nozari , N. Behrouz , T. Azizi , B. Fazlpour

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

A spatially flat Friedmann-Robertson-Walker(FRW) cosmological model with generalized Chaplygin gas is studied in the context of scalar-metric formulation of cosmology. Schutz's mechanism for the perfect fluid is applied with generalized…

General Relativity and Quantum Cosmology · Physics 2011-06-24 Barun Majumder

We show that modelling the universe as a pre-geometric system with emergent quantum modes, and then constructing the classical limit, we obtain a new account of space and gravity that goes beyond Newtonian gravity even in the…

General Physics · Physics 2007-09-20 Reginald T Cahill

We investigate a cosmological model in which dark energy, represented by a quintessential scalar field, is coupled to a dark-matter perfect fluid in the spatially flat Friedmann-Robertson-Walker Universe. This allows an energy exchange in…

General Relativity and Quantum Cosmology · Physics 2023-08-22 Yousef Bisabr

In this paper, we introduce a non-minimally conformally coupled scalar field and dark matter in F(T) cosmology and study their dynamics. We investigate the stability and phase space behavior of the parameters of the scalar field by choosing…

General Relativity and Quantum Cosmology · Physics 2012-08-02 Mubasher Jamil , D. Momeni , Ratbay Myrzakulov

In this letter we investigate acceleration in the flat cosmological model with a conformally coupled phantom field and we show that acceleration is its generic feature. We reduce the dynamics of the model to a 3-dimensional dynamical system…

High Energy Physics - Theory · Physics 2008-11-26 Orest Hrycyna , Marek Szydlowski

Dipole cosmology is the maximally Copernican generalization of the FLRW paradigm that can incorporate bulk flows in the cosmic fluid. In this paper, we first discuss how multiple fluid components with independent flows can be realized in…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-24 Ehsan Ebrahimian , Chethan Krishnan , Ranjini Mondol , M. M. Sheikh-Jabbari

Cosmological models with two interacting fluids, each satisfying the strong energy condition, are studied in the framework of classical General Relativity. If the interactions are phenomenologically described by a power law in the scale…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Nelson Pinto-Neto , Bernardo M. O. Fraga

We revisit the evolution of the scale factor in a flat FRW spacetime with a new generalized decay rule for the dynamic $\Lambda$-term under modified theories of gravity. It analyses certain cosmological parameters and examines their…

General Physics · Physics 2021-08-02 Anirudh Pradhan , De Avik , Tee How Loo , D. C. Maurya

We study a model in which a closed universe with dust and quintessence matter components may look like an accelerated flat Friedmann-Robertson-Walker (FRW) universe at low redshifts. Several quantities relevant to the model are expressed in…

Astrophysics · Physics 2009-11-10 Sergio del Campo , Mauricio Cataldo , Francisco Pena

We discuss some cosmological consequences of a general model of coupled quintessence in which the phenomenological coupling between the cold dark matter and dark energy is a function of the cosmic scale factor $\epsilon(a)$. This class of…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-23 F. E. M. Costa

Cosmological observations of the recent universe suggest that dark energy equation of state parameter $w$ is growing with time, departing from a cosmological constant for which $w=-1$. Standard quintessence models allow for a varying…

High Energy Physics - Theory · Physics 2025-07-11 David Andriot

We explore the properties of dark energy models for which the equation-of-state, w, defined as the ratio of pressure to energy density, crosses the cosmological-constant boundary w = -1. We adopt an empirical approach, treating the dark…

Astrophysics · Physics 2010-04-06 Robert R. Caldwell , Michael Doran

In this paper, we investigate the background dynamics in brane cosmology when dark energy is coupled to dark matter by a suitable interaction. Here we consider an homogeneous and isotropic Friedmann-Robertson-Walker (FRW) brane model and…

General Relativity and Quantum Cosmology · Physics 2015-02-25 Sujay Kr. Biswas , Subenoy Chakraborty

In a very recent paper, the current authors (arXiv:gr-qc/1609.01477) have proposed and analyzed in detail the logarithmic form of Brans-Dicke scalar field $\phi$ as $\phi \propto ln(\alpha+\beta a)$, where $\alpha$ and $\beta$ are positive…

General Relativity and Quantum Cosmology · Physics 2017-06-13 Pankaj Kumar , C. P. Singh

Inspired from the idea of minimally coupling of a real scalar field to geometry, we investigate the classical and quantum models of a flat energy-dependent FRW cosmology coupled to a perfect fluid in the framework of the scalar-rainbow…

General Relativity and Quantum Cosmology · Physics 2016-04-26 M. Khodadi , K. Nozari , B. Vakili