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arXiv · 1706.01706

Cosmological constraints on a unified dark matter-energy scalar field model with fast transition

Iker Leanizbarrutia·Alberto Rozas-Fernández·Ismael Tereno
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Abstract

We test the viability of a single fluid cosmological model containing a transition from a dark-matter-like regime to a dark-energy-like regime. The fluid is a k-essence scalar field with a well-defined Lagrangian. We constrain its model parameters with a combination of geometric probes and conclude that the evidence for this model is similar to the evidence for $\Lambda$CDM. In addition, we find a lower bound for the rapidity of the transition, implying that fast transitions are favored with respect to slow ones even at background level.

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Iker Leanizbarrutia, Alberto Rozas-Fernández, Ismael Tereno. 2017-06-06. Cosmological constraints on a unified dark matter-energy scalar field model with fast transition. https://doi.org/10.1103/physrevd.96.023503

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