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Dark Energy and Viscous Cosmology

I. Brevik·O. Gorbunova
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Abstract

Singularities in the dark energy universe are discussed, assuming that there is a bulk viscosity in the cosmic fluid. In particular, it is shown how the physically natural assumption of letting the bulk viscosity be proportional to the scalar expansion in a spatially flat FRW universe can drive the fluid into the phantom region (w < -1), even if lies in the quintessence region (w > -1) in the non-viscous case.

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I. Brevik, O. Gorbunova. 2005-08-11. Dark Energy and Viscous Cosmology. https://doi.org/10.1007/s10714-005-0178-9

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