Dynamics of interacting quintessence

There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

Abstract

In this paper, we investigate coupled quintessence with scaling potential assuming specific forms of the coupling as \(A\) namely, \(\alpha \dot{\rho_m}\), \(\beta \dot{\rho_{\phi}}\) and \(\sigma (\dot{\rho_m}+\dot{\rho_{\phi}})\), and present phase space analysis for three different interacting models. We focus on the attractor solutions that can give rise to late time acceleration with \(\Omega_{DE}/\Omega_{DM}\) of order unity in order to alleviate the coincidence problem.

Related collections

Most cited references 4

Record: found
Abstract: not found
Article: not found

Om diagnostic applied to scalar field models and slowing down of cosmic acceleration

M. Shahalam, Abhineet Agarwal, Sasha Sami (2015)

0 comments Cited 13 times – based on 0 reviews      Review now

Bookmark

Record: found
Abstract: found
Article: found

Is Open Access

A tachyonic scalar field with mutually interacting components

Murli Verma, Shankar Pathak (2011)

We investigate the tachyonic cosmological potential \(V(\phi)\) in two different cases of the quasi-exponential expansion of universe and discuss various forms of interaction between the two components---matter and the cosmological constant--- of the tachyonic scalar field, which leads to the viable solutions of their respective energy densities. The distinction among the interaction forms is shown to appear in the \(O_{m}(x)\) diagnostic. Further, the role of the high- and low-redshift observations of the Hubble parameter is discussed to determine the proportionality constants and hence the correct form of matter--cosmological constant interaction.

0 comments Cited 9 times – based on 0 reviews

Preprint

     Review now

Bookmark

Record: found
Abstract: found
Article: found

Is Open Access

K-Chameleon and the Coincidence Problem

Rong-Gen Cai, Hao Wei (2004)

In this paper we present a hybrid model of k-essence and chameleon, named as k-chameleon. In this model, due to the chameleon mechanism, the directly strong coupling between the k-chameleon field and matters (cold dark matters and baryons) is allowed. In the radiation dominated epoch, the interaction between the k-chameleon field and background matters can be neglected, the behavior of the k-chameleon therefore is the same as that of the ordinary k-essence. After the onset of matter domination, the strong coupling between the k-chameleon and matters dramatically changes the result of the ordinary k-essence. We find that during the matter-dominated epoch, only two kinds of attractors may exist: one is the familiar {\bf K} attractor and the other is a completely {\em new}, dubbed {\bf C} attractor. Once the universe is attracted into the {\bf C} attractor, the fraction energy densities of the k-chameleon \(\Omega_{\phi}\) and dust matter \(\Omega_m\) are fixed and comparable, and the universe will undergo a power-law accelerated expansion. One can adjust the model so that the {\bf K} attractor do not appear. Thus, the k-chameleon model provides a natural solution to the cosmological coincidence problem.