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On homothetic cosmological dynamics

Rinat A. Daishev·Winfried Zimdahl
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Abstract

We consider the homogeneous and isotropic cosmological fluid dynamics which is compatible with a homothetic, timelike motion, equivalent to an equation of state $ρ+ 3P = 0$. By splitting the total pressure $P$ into the sum of an equilibrium part $p$ and a non-equilibrium part $Π$, we find that on thermodynamical grounds this split is necessarily given by $p = ρ$ and $Π= - (4/3)ρ$, corresponding to a dissipative stiff (Zel'dovich) fluid.

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Rinat A. Daishev, Winfried Zimdahl. 2003-09-25. On homothetic cosmological dynamics. https://doi.org/10.1088/0264-9381%2F20%2F23%2F005

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