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The Unified Equation of State for Dark Matter and Dark Energy

Wei Wang·Yuan-xing Gui·Suhong Zhang·Guanghai Guo·Ying Shao
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Abstract

We assume that dark matter and dark energy satisfy the unified equation of state: $p=B(z)ρ$, with $p=p_{dE}$, $ρ=ρ_{dm}+ρ_{dE}$, where the pressure of dark matter $p_{dm}=0$ has been taken into account. A special function $B=-\frac{A}{(1+z)^α}$ is presented, which can well describe the evolution of the universe. In this model, the universe will end up with a Big Rip. By further simple analysis, we know other choices of the function $B$ can also describe the universe but lead to a different doomsday.

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Wei Wang, Yuan-xing Gui, Suhong Zhang, Guanghai Guo, Ying Shao. 2005-04-05. The Unified Equation of State for Dark Matter and Dark Energy. https://doi.org/10.1142/s0217732305016877

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