Viscosity in modified gravity

Iver Brevik

doi:10.3390/e14112302

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arXiv · 1211.2562

Viscosity in modified gravity

Iver Brevik

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Abstract

A bulk viscosity is introduced in the formalism of modified gravity. It is shown that, on the basis of a natural scaling law for the viscosity, a simple solution can be found for quantities such as the Hubble parameter and the energy density. These solutions may incorporate a viscosity-induced Big Rip singularity. By introducing a phase transition in the cosmic fluid, the future singularity can nevertheless in principle be avoided.

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Iver Brevik. 2012-11-23. Viscosity in modified gravity. https://doi.org/10.3390/e14112302

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