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arXiv · 1212.2360

Generalized Semi-Holographic Universe

Hui Li·Hongsheng Zhang·Yi Zhang
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Abstract

We study the semi-holographic idea in context of decaying dark components. The energy flow between dark energy and the compensating dark matter is thermodynamically generalized to involve a particle number variable dark component with non-zero chemical potential. It's found that, unlike the original semi-holographic model, no cosmological constant is needed for a dynamical evolution of the universe. A transient phantom phase appears while a non-trivial dark energy-dark matter scaling solution keeps at late time, which evades the big-rip and helps to resolve the coincidence problem. For reasonable parameters, the deceleration parameter is well consistent with current observations. The original semi-holographic model is extended and it also suggests that the concordance model may be reconstructed from the semi-holographic idea.

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Hui Li, Hongsheng Zhang, Yi Zhang. 2012-12-11. Generalized Semi-Holographic Universe. https://doi.org/10.1088/0256-307x%2F30%2F8%2F089801

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