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Cosmology with a Variable Chaplygin Gas

Zong-Kuan Guo·Yuan-Zhong Zhang
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Abstract

We consider a new generalized Chaplygin gas model that includes the original Chaplygin gas model as a special case. In such a model the generalized Chaplygin gas evolves as from dust to quiessence or phantom. We show that the background evolution for the model is equivalent to that for a coupled dark energy model with dark matter. The constraints from the current type Ia supernova data favour a phantom-like Chaplygin gas model.

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Zong-Kuan Guo, Yuan-Zhong Zhang. 2007-01-09. Cosmology with a Variable Chaplygin Gas. https://doi.org/10.1016/j.physletb.2006.12.063

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