Viscosity in Modified Gravity
نویسنده
چکیده
A bulk viscosity is introduced in the formalism of modified gravity. It is shown that, based on 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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عنوان ژورنال:
- Entropy
دوره 14 شماره
صفحات -
تاریخ انتشار 2012