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Related papers: Role of Chameleon Field in Accelerating Universe

200 papers

In the present research article, we have studied the flat FRW space time with domain wall and holographic dark energy in the context of $f(Q)$ theory of gravity. The exact solutions of the field equations are obtained using two different…

General Relativity and Quantum Cosmology · Physics 2024-10-11 S. P. Hatkar , D. P. Tadas , S. D. Katore

A generalized version for the Rastall theory is proposed showing the agreement with the cosmic accelerating expansion. In this regard, a coupling between geometry and the pressureless matter fields is derived which may play the role of dark…

General Relativity and Quantum Cosmology · Physics 2017-05-24 H. Moradpour , Y. Heydarzade , F. Darabi , Ines G. Salako

In this article, we study the expanding nature of universe in the contest of $f(R,L_m)$ gravity theory, here $ R $ represents the Ricci scalar and $ L_m $ is the matter Lagrangian density. With a specific form of $ f(R,L_m) $, we obtain the…

General Relativity and Quantum Cosmology · Physics 2023-06-28 J. K. Singh , Shaily , Ratbay Myrzakulov , Harshna Balhara

We analyse the PVLAS results using a chameleon field whose properties depend on the environment. We find that, assuming a runaway bare potential $V(\phi)$ and a universal coupling to matter, the chameleon potential is such that the scalar…

High Energy Physics - Phenomenology · Physics 2008-11-26 Ph. Brax , C. van de Bruck , A. -C. Davis

A new cosmological scenario driven by a slow rolling homogeneous scalar field whose exponential potential $V(\Phi)$ has a quadratic dependence on the field $\Phi$ in addition to the standard linear term is discussed. The derived equation of…

Astrophysics · Physics 2009-11-11 F. C. Carvalho , J. S. Alcaniz , J. A. S. Lima , R. Silva

A review on spatially flat D-dimensional Friedmann-Robertson-Walker (FRW) model of the universe has been performed. Some standard parameterizations of the equation of state parameter of the Dark Energy models are proposed and the…

General Relativity and Quantum Cosmology · Physics 2019-03-26 Tanwi Bandyopadhyay , Ujjal Debnath

In this work we consider the evolution of the interactive dark fluids in the background of homogeneous and isotropic FRW model of the universe. The dark fluids consist of a warm dark matter and a dark energy and both are described as…

General Relativity and Quantum Cosmology · Physics 2013-10-01 Supriya Pan , Subenoy Chakraborty

A model for the universe with tachyonic and fermionic fields interacting through a Yukawa-type potential is investigated. It is shown that the tachyonic field answers for the initial accelerated regime and for the subsequent decelerated…

General Relativity and Quantum Cosmology · Physics 2016-02-23 Marlos O. Ribas , Fernando P. Devecchi , Gilberto M. Kremer

We consider Brans-Dicke type nonminimally coupled scalar field as a candidate for dark energy. In the conformally transformed Einstein's frame, our model is similar to {\it coupled quintessence} model. In such models, we consider potentials…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-14 Anjan A Sen , Gaveshna Gupta , Sudipta Das

In this paper, we study the model of the late universe with the homogeneous, isotropic and flat Friedmann-Robertson-Walker metric, where the source of the gravitational field is based on the fermion and boson field, with the Maxwell term…

General Relativity and Quantum Cosmology · Physics 2020-07-13 O. Razina , P. Tsyba , B. Meirbekov , R. Myrzakulov

We study the late time evolution of flat and negatively curved FRW models with a perfect fluid matter source and a scalar field having an arbitrary non-negative potential function $V(\phi) .$ We prove using a dynamical systems approach four…

General Relativity and Quantum Cosmology · Physics 2009-11-10 John Miritzis

Atom interferometry experiments are searching for evidence of chameleon scalar fields with ever-increasing precision. As experiments become more precise, so too must theoretical predictions. Previous work has made numerous approximations to…

Cosmology and Nongalactic Astrophysics · Physics 2016-08-31 Benjamin Elder , Justin Khoury , Philipp Haslinger , Matt Jaffe , Holger Müller , Paul Hamilton

We present a simple higher dimensional FRW type of model where the acceleration is apparently caused by the presence of the extra dimensions. Assuming an ansatz in the form of the deceleration parameter we get a class of solutions some of…

General Relativity and Quantum Cosmology · Physics 2009-11-11 S. Chatterjee , A. Banerjee , Y. Z. Zhang

We study the dynamics of the scalar field FLRW flat cosmological models within the framework of the Unified Dark Matter (UDM) scenario. In this model we find that the main cosmological functions such as the scale factor of the Universe, the…

Astrophysics · Physics 2010-04-23 S. Basilakos , G. Lukes-Gerakopoulos

The work deals with homogeneous and isotropic, flat FRW model of the universe which is filled up with non-interacting dark matter and dark energy to compatible with recent observational evidences. By choosing the dark energy in the form of…

General Relativity and Quantum Cosmology · Physics 2013-05-09 Nilanjana Mahata , Subenoy Chakraborty

In this work we investigate the evolution of a Universe consisted of a scalar field, a dark matter field and non-interacting baryonic matter and radiation. The scalar field, which plays the role of dark energy, is non-minimally coupled to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. B. Binder , G. M. Kremer

We study the coincidence problem of late cosmic acceleration by assuming that the present ratio between dark matter and dark energy is a slowly varying function of the scale factor. As dark energy component we consider two different…

Astrophysics · Physics 2009-11-13 Sergio del campo , Ramon Herrera , Diego Pavon

We study the impact of the chameleon mechanism on the structure of white dwarfs. Using a shooting method of our design, we solve the corresponding scalar-tensor equilibrium equations for a Chandrasekhar equation of state, exploring various…

General Relativity and Quantum Cosmology · Physics 2025-08-05 Joan Bachs-Esteban , Ilídio Lopes , Javier Rubio

We examine in the context of general relativity the dynamics of a spatially flat Robertson-Walker universe filled with a classical minimally coupled scalar field \phi of exponential potential ~ e^{-\mu\phi} plus pressureless baryonic…

General Relativity and Quantum Cosmology · Physics 2009-11-10 A. Kehagias , G. Kofinas

We have developed an accelerating cosmological model for the present universe which is phantom for the period $ (0 \leq z \leq 1.99)$ and quintessence phase for $(1.99 \leq z \leq 2.0315)$. The universe is assumed to be filled with…

General Relativity and Quantum Cosmology · Physics 2021-08-02 G. K. Goswami , Anirudh Pradhan , A. Beesham