Cosmic acceleration in non-canonical scalar field model: an interacting scenario

Abstract

In this paper we have studied the dynamics of accelerating scenario within the framework of scalar field models possessing a non-canonical kinetic term. In this toy model, the scalar field is allowed to interact with the dark matter component through a source term. We have assumed a specific form for the coupling term and then have studied the dynamics of the scalar field having a constant equation of state parameter. We have also carried out the dynamical system study of such interacting non-canonical scalar field models for power law potentials for some physically relevant specific values of the model parameters. It has been found that the only for two particular stable fixed points of the system, an accelerating solution is possible and the universe will settle down to a CDM universe in future and thus there is no future singularity in this model.

Study of non-canonical scalar field model using various parametrizations of dark energy equation of state

“…It is also worth mentioning that the Lagrangian (8) differs from the Lagrangian of k-essence and phantom models in the sense that for phantom field kinetic energy term itself is negative and here the potential term is non-zero. This type of Lagrangian has also been considered in our earlier work [60]. In the subsequent sections, we try to build up an accelerating model for the universe in which the non-canonical scalar field will play the role of dynamical dark energy.…”

“…Later, Chiba et al [13] introduced this scenario for dark energy models. In our recent work [60], we have studied an interacting noncanonical scalar field model with a constant EoS parameter for the scalar field. The model was however restricted in the sense that a constant EoS parameter does not provide a general framework.…”

Generalized second law of thermodynamics for non-canonical scalar field model with corrected-entropy

“…The cosmological aspects of this model has already been studied by the authors in an earlier work [11]. In the present work, we investigate the validity of GSL of thermodynamics for the non-canonical model at both the apparent horizon and the event horizon.…”

“…However, for most of the dark energy models the analysis is carried out for canonical scalar fields. But there is another class of scalar field models, viz, non-canonical scalar field models which have also been considered as a candidate for dark energy (for details see [11][12][13] and the references there in). This class of models has also been found to be a very good candidate for dark energy and could provide solution to a number of cosmological problems.…”

A Study of Non-Canonical Lagrangian

“…In recent years, non canonical Lagrangian density has been used in the inflationary cosmological models [6]- [8] (see ref. [9] for further details). In the context of cosmological model, even in absence of any potential energy term, a general class of non-standard (i.e., non-quadratic) kinetic energy terms ( ) φ   , for a scalar field φ , can drive an inflationary evolution of the same type as the usually considered potential driven inflation.…”