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arXiv · 1104.4758

Reconstructing the expansion history of the Universe with a one-fluid approach

Orlando Luongo·Hernando Quevedo
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Abstract

Assuming that the Universe is filled by one single fluid, we present in the context of General Relativity a possible explanation for the acceleration of the Universe. We use ordinary thermodynamics and the fact that small matter perturbations barely propagate in our Universe, to derive a general solution for a single fluid in which the speed of sound vanishes. We find a model that contains $\Lambda$CDM as a special case, and is compatible with current observational data.

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Orlando Luongo, Hernando Quevedo. 2011-04-25. Reconstructing the expansion history of the Universe with a one-fluid approach. https://arxiv.org/abs/1104.4758

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