Eur. Phys. J. C (2015) 75: 43
https://doi.org/10.1140/epjc/s10052-015-3263-6

Regular Article - Theoretical Physics

Higher order corrections of the extended Chaplygin gas cosmology with varying and

¹ Physics Department, Istanbul Technical University, Istanbul, Turkey
² Max Planck Institute of Colloids and Interfaces, Potsdam-Golm Science Park Am Mhlenberg 1 OT Golm, 14476, Potsdam, Germany
³ School of Physics, Damghan University, Damghan, Iran
⁴ Eurasian International Center for Theoretical Physics, Eurasian National University, Astana, 010008, Kazakhstan
⁵ Department of Physics, University of Trieste, Via Valerio, 2, 34127, Trieste, Italy

^* e-mail: b.pourhassan@du.ac.ir

Received: 15 October 2014
Accepted: 3 January 2015
Published online: 3 February 2015

Abstract

In this paper, we study two different models of dark energy based on the Chaplygin gas equation of state. The first model is the variable modified Chaplygin gas, while the second one is the extended Chaplygin gas. Both models are considered in the framework of higher order modified gravity. We also consider the case of time-varying gravitational constant and for both models. We investigate some cosmological parameters such as the Hubble, the deceleration, and the equation of state parameters. Then we show that the model that we consider, the extended Chaplygin gas with time-dependent and , is consistent with the observational data. Finally we conclude with the discussion of cosmological perturbations of our model.