Thermodynamics of Modified Cosmic Chaplygin Gas

M Sharif,Sara Ashraf

doi:10.1155/2018/8949252

Abstract

We examine the thermodynamic features of an exotic fluid known as modified cosmic Chaplygin gas in the context of homogeneous isotropic universe model. For this purpose, the behavior of physical parameters is discussed that help to analyze nature of the universe. Using specific heat formalism, the validity of third law of thermodynamics is checked. Furthermore, with the help of thermodynamic entities, the thermal equation of state is also discussed. The thermodynamic stability is explored by means of adiabatic, specific heat and isothermal conditions from classical thermodynamics. It is concluded that the considered fluid configuration is thermodynamically stable and expands adiabatically for an appropriate choice of parameters.

Highlights

The discovery of accelerated expansion of the universe has unambiguously been proved by a diverse set of high-precision observational data accumulated from various astronomical sources [1,2,3]
We have examined the expanding evolution of the universe through different physical parameters like pressure, effective equation of state (EoS), and deceleration parameters as well as speed of sound
The results of these parameters can be summarized as follows: (i) The consistent behavior of pressure with the evolutionary picture of the universe is obtained for the considered values of Z whereas inconsistent evolution is observed for its positive values (Figure 1)

Summary

Introduction

The discovery of accelerated expansion of the universe has unambiguously been proved by a diverse set of high-precision observational data accumulated from various astronomical sources [1,2,3]. Chaplygin gas is an intriguing model presented by a Russian physicist Chaplygin as a convenient soluble model to study the lifting force on the wing of an aeroplane in aerodynamics It efficiently describes the cosmic expansion and elegantly discusses DM and DE in a unified form. Gonzalez-Dıaz [15] proposed the generalization of cosmic CG models known as generalized cosmic Chaplygin gas (GCCG) in such a way that it avoids big-rip (singularity at a finite time) which was previously presented in the DE models representing phantom era. This generalization provides stable and physical behavior models even when the vacuum matter configuration.

Physical Parameters for MCCG

Thermodynamic Stability

Findings

Conclusions