scholarly journals Tachyonic field interacting with scalar (phantom) field

2009 ◽  
Vol 39 (1) ◽  
Author(s):  
Surajit Chattopadhyay ◽  
Ujjal Debnath
2010 ◽  
Vol 88 (12) ◽  
pp. 933-938 ◽  
Author(s):  
Surajit Chattopadhyay ◽  
Ujjal Debnath

In the present work, we consider the tachyonic field, the phantom field, and the scalar field in both interacting and non-interacting situations and investigate the validity of the generalized second law of thermodynamics in a flat FRW universe. We find that in all cases, except for the phantom field dominated universe, the derivative of the entropy remains at negative level and increases with the decrease in redshift.


2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Nayem Sk ◽  
Abhik Kumar Sanyal

It has been shown earlier that Noether symmetry does not admit a form of corresponding to an action in which is coupled to scalar-tensor theory of gravity or even for pure theory of gravity taking anisotropic model into account. Here, we prove that theory of gravity does not admit Noether symmetry even if it is coupled to tachyonic field and considering a gauge in addition. To handle such a theory, a general conserved current has been constructed under a condition which decouples higher-order curvature part from the field part. This condition, in principle, solves for the scale-factor independently. Thus, cosmological evolution remains independent of the form of the chosen field, whether it is a scalar or a tachyon.


2018 ◽  
Vol 35 (3) ◽  
pp. 035008 ◽  
Author(s):  
Rubén O Acuña-Cárdenas ◽  
J A Astorga-Moreno ◽  
Miguel A García-Aspeitia ◽  
J C López-Domínguez
Keyword(s):  

2019 ◽  
Vol 28 (15) ◽  
pp. 1950170
Author(s):  
Kui Xiao

The evolutionary pictures for phantom field in loop quantum cosmology are discussed in this paper. Comparing the dynamical behaviors of the phantom field with one of the canonical scalar fields in loop quantum cosmology scenario, we found that the [Formula: see text] phase trajectories are the same, but the [Formula: see text] phase-spaces are very different, and the phantom field with considering potentials can drive neither super inflation nor slow-roll inflation in loop quantum cosmology (LQC) scenario. While the universe is filled with multiple dark fluids, to ensure that the condition [Formula: see text] does not violate, the energy density of dark matter [Formula: see text] and the equation-of-state of phantom field [Formula: see text] should satisfy the condition [Formula: see text] at the bounce point. If this constraint condition holds, the universe can enter an inflationary stage, and it is possible to unify the description of phantom field, dark matter and inflation. We introduced a toy model which has the same form of the general Chaplygin gas to unify the dark energy, dark matter and slow-roll inflation, and the slow-roll inflation of the toy model has also been discussed.


2008 ◽  
Vol 23 (04) ◽  
pp. 269-279 ◽  
Author(s):  
BAORONG CHANG ◽  
HONGYA LIU ◽  
LIXIN XU ◽  
CHENGWU ZHANG

We study the statefinder parameter in the five-dimensional big bounce model, and apply it to differentiate the attractor solutions of quintessence and phantom field. It is found that the evolving trajectories of these two attractor solutions in the statefinder parameters plane are quite different, and that are different from the statefinder trajectories of other dark energy models.


2003 ◽  
Vol 68 (2) ◽  
Author(s):  
Parampreet Singh ◽  
M. Sami ◽  
Naresh Dadhich
Keyword(s):  

2014 ◽  
Vol 351 (1) ◽  
pp. 59-65 ◽  
Author(s):  
Hassan Amirhashchi ◽  
Anirudh Pradhan

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