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arXiv · 0803.0281

Equilibrium boundary conditions, dynamic vacuum energy, and the Big Bang

F. R. Klinkhamer
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Abstract

The near-zero value of the cosmological constant Λin an equilibrium context may be due to the existence of a self-tuning relativistic vacuum variable q. Here, a cosmological nonequilibrium context is considered with a corresponding time-dependent cosmological parameter Λ(t) or vacuum energy density ρ_V(t). A specific model of a closed Friedmann-Robertson-Walker universe is presented, which is determined by equilibrium boundary conditions at one instant of time (t=t_{eq}) and a particular form of vacuum-energy dynamics (dρ_V/dt \propto ρ_M). This homogeneous and isotropic model has a standard Big Bang phase at early times (t << t_{eq}) and reproduces the main characteristics of the present universe (t=t_0 < t_{eq}).

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F. R. Klinkhamer. 2008-10-25. Equilibrium boundary conditions, dynamic vacuum energy, and the Big Bang. https://doi.org/10.1103/physrevd.78.083533

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