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arXiv · 1312.3102

Viscosity-Induced Crossing of the Phantom Divide in the Dark Cosmic Fluid

Iver Brevik
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Abstract

Choosing various natural forms for the equation-of-state parameter w and the bulk viscosity \zeta, we discuss how it is possible for a dark energy fluid to slide from the quintessence region across the divide w=-1 into the phantom region, and thus into a Big Rip future singularity. Different analytic forms for \zeta, as powers of the scalar expansion, are suggested and compared with experiments.

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Iver Brevik. 2013-12-11. Viscosity-Induced Crossing of the Phantom Divide in the Dark Cosmic Fluid. https://doi.org/10.3389/fphy.2013.00027

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