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Related papers: Conformally Coupled Tachyonic Dark Energy

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A new model for the universe filled with a generalized Chaplygin fluid is considered which unitarily describes as a single vacuum entity both a quintessence scalar field and a cosmological constant, so unifying the notion of dark energy.…

Astrophysics · Physics 2008-11-26 Pedro F. Gonzalez-Diaz

We assess the viability of successful reconstruction of the evolution of the dark energy equation of state using varying fundamental couplings, such as the fine structure constant or the proton-to-electron mass ratio. We show that the same…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 P. P. Avelino , L. Losano , R. Menezes , J. C. R. E. Oliveira

Inspired by thermodynamical dissipative phenomena, we consider bulk viscosity for dark fluid in a spatially flat two-component Universe. Our viscous dark energy model represents Phantom crossing avoiding Big-Rip singularity. We propose a…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-12 Behrang Mostaghel , Hossein Moshafi , S. M. S. Movahed

Cosmological analysis based on currently available observations are unable to rule out a sizeable coupling between dark energy and dark matter. However, the signature of the coupling is not easy to grasp, since the coupling is degenerate…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-22 Jian-Hua He , Bin Wang , Elcio Abdalla

Scalar-field dark energy models like tachyon are often regarded as an effective description of an underlying theory of dark energy. In this Letter, we implement the interacting agegraphic dark energy models with tachyon field. We…

High Energy Physics - Theory · Physics 2015-05-13 A. Sheykhi

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

Phantom cosmology allows to account for dynamics and matter content of the universe tracing back the evolution to the inflationary epoch, considering the transition to the non-phantom standard cosmology (radiation/matter dominated eras) and…

High Energy Physics - Theory · Physics 2008-11-26 S. Capozziello , S. Nojiri , S. D. Odintsov

The string inspired tachyon field can serve as a candidate of dark energy. Its equation of state parameter $w$ varies from 0 to -1. In case of tachyon field potential $V(\phi)\to 0$ slower(faster) than $1/\phi^2$ at infinity, dark…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-30 Amna Ali , M. Sami , A. A. Sen

The increasing observational pressure on the standard cosmological model motivates analyses going beyond the paradigm of the collision-less cold dark matter (DM). Since the only clear evidence for the existence of DM is based on…

High Energy Physics - Phenomenology · Physics 2022-05-25 Philippe Brax , Carsten van de Bruck , Sebastian Trojanowski

We investigate an interacting dark energy-dark matter model within the quintessence framework, characterized by the coupling term $Q_0 = \alpha \kappa \rho_m \dot{\phi} \left[1 - \beta R/(6H^2) \right]$, and the scalar field evolves under…

General Relativity and Quantum Cosmology · Physics 2025-10-28 Anirban Chatterjee , Yungui Gong

Cosmological models can be studied effectively using dynamical systems techniques. Starting from Brown's formulation of the variational principle for relativistic fluids, we introduce new types of couplings involving a perfect fluid, a…

General Relativity and Quantum Cosmology · Physics 2024-09-13 Christian G. Boehmer , Antonio d'Alfonso del Sordo

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

We analyze scalar field dark energy models minimally and non-minimally coupled to gravity, postulating that a Yukawa-like interacting term is \emph{in form} equivalent for general relativity, teleparallel and symmetric-teleparallel…

General Relativity and Quantum Cosmology · Physics 2025-04-15 Youri Carloni , Orlando Luongo

Recently, the tachyon cosmology has been represented as dark energy model to support the current acceleration of the universe without phantom crossing. In this paper, we study the dynamics of the tachyon cosmology in which the field plays…

General Relativity and Quantum Cosmology · Physics 2015-05-27 H. Farajollahi , A. Ravanpak , G. F. Fadakar

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

Large classes of dark sector models feature mass scales and couplings very different from the ones we observe in the Standard Model (SM). Moreover, in the freeze-in mechanism, often employed by the dark sector models, it is also required…

High Energy Physics - Phenomenology · Physics 2023-03-29 Wen Han Chiu , Sungwoo Hong , Lian-Tao Wang

Cosmological analysis based on currently available observations are unable to rule out a sizeable coupling among the dark energy and dark matter fluids. We explore a variety of coupled dark matter-dark energy models, which satisfy cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-10 Laura Lopez Honorez , Beth A. Reid , Olga Mena , Licia Verde , Raul Jimenez

We have found that the conformally coupled induced gravity can be an infrared fixed point of induced gravity with Yukawa couplings with matter. The late time cosmology with a uniform mean matter distribution can be described by the…

General Relativity and Quantum Cosmology · Physics 2013-09-10 Yongsung Yoon

Assuming a non-gravitational interaction amongst the dark fluids of our universe namely, the dark matter and dark energy, we study a specific interaction model in the background of a spatially flat Friedmann-Lema\^itre-Robertson-Walker…

General Relativity and Quantum Cosmology · Physics 2018-08-29 Weiqiang Yang , Supriya Pan , Ramón Herrera , Subenoy Chakraborty

The problem of the cosmic coincidence is a longstanding puzzle. This conundrum may be solved by introducing a coupling between the two dark sectors. In this Letter, we study two cases of the coupled quintessence scenario. $(a)$ Assume that…

Astrophysics · Physics 2009-11-10 Xin Zhang