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arXiv · 1005.4343

Restrictions on purely kinetic k-essence

Rong-Jia Yang·Xiang-Ting Gao
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Abstract

We restrict purely kinetic k-essence. Assuming the equation of state is a power law of the kinetic energy: $w=w_0X^α$, to obtain accelerated phases, we must have $α>0$ as one of necessary conditions, constrained from the conditions for stability and causality, and the k-essence must behave like phantom. We also study the evolutions of the equation of state and the speed of sound with numerical simulation.

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Rong-Jia Yang, Xiang-Ting Gao. 2010-05-26. Restrictions on purely kinetic k-essence. https://doi.org/10.1088/0256-307x%2F28%2F10%2F109502

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