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Worse than a big rip?

Mariam Bouhmadi-Lopez·Pedro F. Gonzalez-Diaz·Prado Martin-Moruno
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Abstract

We show that a generalised phantom Chaplygin gas can present a future singularity in a finite future cosmic time. Unlike the big rip singularity, this singularity happens for a finite scale factor, but like the big rip singularity, it would also take place at a finite future cosmic time. In addition, we define a dual of the generalised phantom Chaplygin gas which satisfies the null energy condition. Then, in a Randall-Sundrum 1 brane-world scenario, we show that the same kind of singularity at a finite scale factor arises for a brane filled with a dual of the generalised phantom Chaplygin gas.

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Mariam Bouhmadi-Lopez, Pedro F. Gonzalez-Diaz, Prado Martin-Moruno. 2007-10-30. Worse than a big rip?. https://doi.org/10.1016/j.physletb.2007.10.079

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