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Interacting Chaplygin gas

Hongsheng Zhang·Zong-Hong Zhu
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Abstract

We investigate a kind of interacting Chaplygin gas model in which the Chaplygin gas plays the role of dark energy and interacts with cold dark matter particles. We find that there exists a stable scaling solution at late times with the Universe evolving into a phase of steady state. Furthermore, the effective equation of state of Chaplygin gas may cross the so-called phantom divide $w=-1$. The above results are derived from continuity equations, which means that they are independent of any gravity theories. Assuming standard general relativity and a spatially flat FRW metric, we also find the deceleration parameter is well consistent with current observations.

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Hongsheng Zhang, Zong-Hong Zhu. 2006-02-27. Interacting Chaplygin gas. https://doi.org/10.1103/physrevd.73.043518

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