FIVE-DIMENSIONAL COSMOLOGICAL SCALING SOLUTION

A five-dimensional Ricci-flat cosmological solution is studied by assuming that the induced 4D matter contains two components: the usual fluid for dark matter as well as baryons and a scalar field with an exponential potential for dark energy. With use of the phase-plane analysis it is shown that there exist two late-time attractors one of which corresponds to a universe dominated by the scalar field alone and the other is a scaling solution in which the energy density of the scalar field remains proportional to that of the dark matter. It is furthermore shown that for this 5D scaling solution the universe expands with the same rate as in the 4D FRW models and not relies on which 4D hypersurface the universe is located in the 5D manifold.

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THE EVOLUTION OF THE UNIVERSE WITH THE B–I TYPE PHANTOM SCALAR FIELD

International Journal of Modern Physics D ◽

10.1142/s0218271806008231 ◽

2006 ◽

Vol 15 (02) ◽

pp. 199-214 ◽

Cited By ~ 36

Author(s):

WEI FANG ◽

H. Q. LU ◽

Z. G. HUANG ◽

K. F. ZHANG

Keyword(s):

Scalar Field ◽

State Parameter ◽

Phase Plane Analysis ◽

Density Parameter ◽

Late Time ◽

Plane Analysis ◽

Accelerating Expansion ◽

Phantom Scalar ◽

Expansion Of The Universe ◽

The Universe

We consider the phantom cosmology with a Lagrangian [Formula: see text] originated from the nonlinear Born–Infeld type scalar field. This cosmological model can explain the accelerating expansion of the universe with the equation of state parameter w ≤ -1. We get a sufficient condition for an arbitrary potential that admits a late time attractor solution: the value of potential u(Xc) at the critical point (Xc, 0) should be maximum and greater than zero. We study a specific potential with the form of [Formula: see text] via phase plane analysis and compute the cosmological evolution by numerical analysis in detail. The results show that the phantom field survives till today (to account for the present observed accelerating expansion) without interfering with the nucleosynthesis of the standard model (the density parameter Ωϕ≃10-12 at the equipartition epoch), and also avoid the future collapse of the universe.

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Quintessence in low-energy effective theory

EPJ Web of Conferences ◽

10.1051/epjconf/201816808004 ◽

2018 ◽

Vol 168 ◽

pp. 08004

Author(s):

Tae Hoon Lee

Keyword(s):

Scalar Field ◽

Effective Potential ◽

Cosmological Solution ◽

Low Energy ◽

Effective Theory ◽

Late Time ◽

Inverse Power Law ◽

Virtual Interactions ◽

The Universe ◽

Gravitational Equations

Considering a theory of Brans-Dicke gravity with general couplings of a heavy field, we derive the low-energy effective theory action in the universe of temperature much lower than the heavy field mass. Gravitational equations and the Brans-Dicke scalar field equation including an effective potential of the scalar field are obtained, which is induced through virtual interactions of the heavy field in the late-time universe. We find a deSitter cosmological solution stemming from the inverse power law effective potential of the scalar field and discuss the possibility that the late time acceleration of our universe can be described by means of the solution.

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CAN BRANS–DICKE SCALAR FIELD ACCOUNT FOR DARK ENERGY AND DARK MATTER?

Modern Physics Letters A ◽

10.1142/s021773230602055x ◽

2006 ◽

Vol 21 (15) ◽

pp. 1241-1248 ◽

Cited By ~ 32

Author(s):

M. ARIK ◽

M. C. ÇALIK

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Scalar Field ◽

Energy Density ◽

Late Time ◽

Energy Contribution ◽

Time Solution ◽

The Universe

By using a linearized non-vacuum late time solution in Brans–Dicke cosmology, we account for the 75% dark energy contribution but not for approximately 23% dark matter contribution to the present day energy density of the universe.

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Interacting Dark Matter andq-Deformed Dark Energy Nonminimally Coupled to Gravity

Advances in High Energy Physics ◽

10.1155/2016/7380372 ◽

2016 ◽

Vol 2016 ◽

pp. 1-17

Author(s):

Emre Dil

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Scalar Field ◽

Theoretical Description ◽

Late Time ◽

Dynamical Structure ◽

Dark Sector ◽

Accelerating Expansion ◽

Stable Attractor ◽

The Universe

In this paper, we propose a new approach to study the dark sector of the universe by considering the dark energy as an emergingq-deformed bosonic scalar field which is not only interacting with the dark matter, but also nonminimally coupled to gravity, in the framework of standard Einsteinian gravity. In order to analyze the dynamic of the system, we first give the quantum field theoretical description of theq-deformed scalar field dark energy and then construct the action and the dynamical structure of this interacting and nonminimally coupled dark sector. As a second issue, we perform the phase-space analysis of the model to check the reliability of our proposal by searching the stable attractor solutions implying the late-time accelerating expansion phase of the universe.

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Time-varying q-deformed dark energy interacts with dark matter

International Journal of Modern Physics D ◽

10.1142/s0218271817501772 ◽

2017 ◽

Vol 27 (01) ◽

pp. 1750177

Author(s):

Emre Dil ◽

Erdinç Kolay

Keyword(s):

Dark Matter ◽

Dark Energy ◽

Scalar Field ◽

Particle Creation ◽

State Parameter ◽

Late Time ◽

Dynamical Structure ◽

Stable Attractor ◽

Energy Quantum ◽

The Universe

We propose a new model for studying the dark constituents of the universe by regarding the dark energy as a [Formula: see text]-deformed scalar field interacting with the dark matter, in the framework of standard general relativity. Here we assume that the number of particles in each mode of the [Formula: see text]-deformed scalar field varies in time by the particle creation and annihilation. We first describe the [Formula: see text]-deformed scalar field dark energy quantum-field theoretically, then construct the action and the dynamical structure of these interacting dark sectors, in order to study the dynamics of the model. We perform the phase space analysis of the model to confirm and interpret our proposal by searching the stable attractor solutions implying the late-time accelerating phase of the universe. We then obtain the result that when interaction and equation-of-state parameter of the dark matter evolve from the present day values into a particular value, the dark energy turns out to be a [Formula: see text]-deformed scalar field.

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INDUCED PHANTOM AND 5D ATTRACTOR SOLUTION IN SPACETIME–MATTER THEORY

Modern Physics Letters A ◽

10.1142/s0217732305017366 ◽

2005 ◽

Vol 20 (26) ◽

pp. 1973-1981 ◽

Cited By ~ 17

Author(s):

HONGYA LIU ◽

HUANYING LIU ◽

BAORONG CHANG ◽

LIXIN XU

Keyword(s):

Phase Plane ◽

Phase Plane Analysis ◽

Late Time ◽

Plane Analysis ◽

Spacetime Singularity ◽

Attractor Solution ◽

Matter Theory ◽

Cosmological Solutions ◽

The Stability ◽

Induced Matter

In Spacetime–Matter theory we assume that the 4D induced matter of the 5D Ricci-flat bouncing cosmological solutions contains a perfect fluid as well as an induced scalar field. Then we show that the conventional 4D quintessence and phantom models of dark energy could be recovered from the 5D cosmological solutions. By using the phase-plane analysis to study the stability of evolution of the 5D models, we find that the conventional 4D late-time attractor solution is also recovered. This attractor solution shows that the scale factors of the phantom dominated universes in both the 4D and 5D theories will reach infinity in a finite time and the universes will be ended at a new kind of spacetime singularity at which everything will be annihilated. We also find that the repulsive force of the phantom may provide us with a mechanics to explain the bounce.

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