Reduced modified Chaplygin gas cosmology

Understand

In this paper, we study cosmologies containing the reduced modified Chaplygin gas (RMCG) fluid which is reduced from the modified Chaplygin gas $p=A\rho-B\rho^{-\alpha}$ for the value of $\alpha=-1/2$.

• In this special case, dark cosmological models can be realized for different values of model parameter $A$.
• We investigate the viabilities of these dark cosmological models by discussing the evolutions of cosmological quantities and using the currently available cosmic observations.
• It is shown that the special RMCG model ($A=0$ or $A=1$) which unifies the dark matter and dark energy should be abandoned.