scholarly journals Crossing the phantom barrier with purely kinetic multiple k-essence

2006 ◽  
Vol 639 (6) ◽  
pp. 591-595 ◽  
Author(s):  
Luis P. Chimento ◽  
Ruth Lazkoz
Keyword(s):  
Phantom Barrier

scholarly journals Viscosity-Induced Crossing of the Phantom Barrier

Entropy ◽  
2015 ◽  
Vol 17 (12) ◽  
pp. 6318-6328 ◽  
Author(s):  
Iver Brevik
Keyword(s):  
Phantom Barrier

scholarly journals POWER-LAW ENTROPY CORRECTED NEW HOLOGRAPHIC SCALAR FIELD MODELS OF DARK ENERGY WITH MODIFIED IR-CUTOFF

2011 ◽  
Vol 26 (33) ◽  
pp. 2487-2499 ◽  
Author(s):  
A. KHODAM-MOHAMMADI
Keyword(s):  
Dark Energy ◽  
Scalar Field ◽  
Kinetic Energy ◽  
Holographic Dark Energy ◽  
Matter Field ◽  
Dark Energy Density ◽  
Energy Models ◽  
Scalar Field Models ◽  
Phantom Barrier ◽  
Limiting Case

In this work, the PLECHDE model with Granda–Oliveros (G–O) IR-cutoff is studied. The evolution of dark energy density, deceleration and EoS parameters are calculated. I demonstrate that under a condition, our universe can accelerate near the phantom barrier at present time. We calculate these parameters also in PLECHDE at Ricci scale, when α = 2 and β = 1, and a comparison between Ricci scale, G–O cutoff and non-corrected HDE without matter field with G–O cutoff is done. The correspondence between this model and some scalar field of dark energy models is established. By this method, the evolutionary treatment of kinetic energy and potential for quintessence, tachyon, K-essence and dilaton fields, are obtained. I show that the results has a good compatibility with previous work in the limiting case of flat, dark dominated and non-corrected holographic dark energy.

The Phantom Barrier: Ostwallbau 1944-1945

2001 ◽  
Vol 8 (4) ◽  
pp. 442-467
Author(s):  
A. Noble
Keyword(s):  
Phantom Barrier

scholarly journals f(R,T)-Gravity Model with Perfect Fluid Admitting Einstein Solitons

Mathematics ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 82
Author(s):  
Mohd Danish Siddiqi ◽  
Sudhakar K. Chaubey ◽  
Mohammad Nazrul Islam Khan
Keyword(s):  
Vector Field ◽  
Equation Of State ◽  
Perfect Fluid ◽  
Gravity Model ◽  
Ricci Tensor ◽  
Field Equations ◽  
Metric Tensor ◽  
Research Article ◽  
Phantom Barrier ◽  
Liouville’S Equation

f(R,T)-gravity is a generalization of Einstein’s field equations (EFEs) and f(R)-gravity. In this research article, we demonstrate the virtues of the f(R,T)-gravity model with Einstein solitons (ES) and gradient Einstein solitons (GES). We acquire the equation of state of f(R,T)-gravity, provided the matter of f(R,T)-gravity is perfect fluid. In this series, we give a clue to determine pressure and density in radiation and phantom barrier era, respectively. It is proved that if a f(R,T)-gravity filled with perfect fluid admits an Einstein soliton (g,ρ,λ) and the Einstein soliton vector field ρ of (g,ρ,λ) is Killing, then the scalar curvature is constant and the Ricci tensor is proportional to the metric tensor. We also establish the Liouville’s equation in the f(R,T)-gravity model. Next, we prove that if a f(R,T)-gravity filled with perfect fluid admits a gradient Einstein soliton, then the potential function of gradient Einstein soliton satisfies Poisson equation. We also establish some physical properties of the f(R,T)-gravity model together with gradient Einstein soliton.

scholarly journals Mimetic-metric-torsion with induced axial mode and phantom barrier crossing

2021 ◽  
Vol 81 (4) ◽  
Author(s):  
Sourav Sur ◽  
Ashim Dutta ◽  
Hiyang Ramo Chothe
Keyword(s):  
Scalar Field ◽  
Conformal Symmetry ◽  
Red Shift ◽  
Dark Sector ◽  
Axial Mode ◽  
Evolution Of The Universe ◽  
Parity Symmetry ◽  
Phantom Barrier ◽  
Pseudo Scalar ◽  
The Universe

AbstractWe extend the basic formalism of mimetic-metric-torsion gravity theory, in a way that the mimetic scalar field can manifest itself geometrically as the source of not just the trace mode of torsion, but its axial (or, pseudo-trace) mode as well. Specifically, we consider the mimetic field to be (i) coupled explicitly to the well-known Holst extension of the Riemann–Cartan action, and (ii) identified with the square of the associated Barbero–Immirzi field, presumably a pseudo-scalar. The conformal symmetry originally prevaling in the theory would still hold, as the associated Cartan transformations do not affect the torsion pseudo-trace, and hence the Holst term. Demanding the theory to preserve the spatial parity symmetry as well, we show a geometric unification of the cosmological dark sector, and the feasibility of a super-accelerating regime in the course of evolution of the universe. From the observational perspective, assuming the cosmological evolution profile to be very close to that for $$\varLambda $$ Λ CDM, we further illustrate a smooth crossing of the so-called phantom barrier at a low red-shift, albeit with a restricted parametric domain. Subsequently, we determine the extent of the super-acceleration by examining the evolution of the relevant torsion parameters.

scholarly journals On the phantom barrier crossing and the bounds on the speed of sound in non-minimal derivative coupling theories

2018 ◽  
Vol 35 (7) ◽  
pp. 075005 ◽  
Author(s):  
Israel Quiros ◽  
Tame Gonzalez ◽  
Ulises Nucamendi ◽  
Ricardo García-Salcedo ◽  
Francisco Antonio Horta-Rangel ◽  
...  
Keyword(s):  
Speed Of Sound ◽  
Barrier Crossing ◽  
Derivative Coupling ◽  
Phantom Barrier

The Phantom Barrier: Ostwallbau 1944-1945

2001 ◽  
Vol 8 (4) ◽  
pp. 442-467
Author(s):  
Alastair Noble
Keyword(s):  
Phantom Barrier
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