Crossing the phantom barrier with purely kinetic multiple k-essence

Luis P. Chimento; Ruth Lazkoz

doi:10.1016/j.physletb.2006.07.017

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arXiv · astro-ph/0604090

Crossing the phantom barrier with purely kinetic multiple k-essence

Luis P. Chimento·Ruth Lazkoz

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Abstract

We consider multiple k-essence sources and obtain the conditions their kinetic functions must satisfy so that purely kinetic k-essences lead to models with phantom barrier crossing. After that, we show that polynomial kinetic functions allow the integration of the dynamical equations determining the geometry and the k-fields. The models thus obtained have accelerated expansion at late cosmic time, representing universes ending at a finite time with a big rip singularity. In addition, these models begin to evolve from an initial singularity, so they have a finite time span.

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Luis P. Chimento, Ruth Lazkoz. 2006-04-05. Crossing the phantom barrier with purely kinetic multiple k-essence. https://doi.org/10.1016/j.physletb.2006.07.017

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