Interacting two-component fluid models with varying EoS parameter

Khurshudyan M., POURHASSAN B., Kahya E. O.

INTERNATIONAL JOURNAL OF GEOMETRIC METHODS IN MODERN PHYSICS, vol.11, no.6, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 11 Issue: 6
  • Publication Date: 2014
  • Doi Number: 10.1142/s0219887814500613
  • Journal Name: INTERNATIONAL JOURNAL OF GEOMETRIC METHODS IN MODERN PHYSICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Keywords: Dark energy, cosmology, early Universe, GENERALIZED CHAPLYGIN-GAS, HUBBLE CONSTANT, DARK ENERGY, CONSTRAINTS
  • Istanbul Technical University Affiliated: Yes

Abstract

In this paper, we consider Universe filled with two-component fluid. We study two different models. In the first model we assume barotropic fluid with the linear equation of state (EoS) as the first component of total fluid. In the second model we assume van der Waals gas as the first component of total fluid. In both models, the second component assumed generalized ghost dark energy. We consider also interaction between components and discuss, numerically, cosmological quantities for two different parametrizations of EoS which varies with time. We consider this as a toy model of our Universe. We fix parameters of the model by using generalized second law of thermodynamics. Comparing our results with some observational data suggests interacting barotropic fluid with EoS parameter omega(t) = omega(0) cos(tH) + omega(1)t(H) over dot/H and generalized ghost dark energy as an appropriate model to describe our Universe.