Equilibrium boundary conditions, dynamic vacuum energy, and the Big Bang
arXiv:0803.0281 · doi:10.1103/PhysRevD.78.083533
Abstract
The near-zero value of the cosmological constant Îin 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 Î(t) or vacuum energy density Ï_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 (dÏ_V/dt \propto Ï_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}).
20 pages with revtex4; v7: published version in preprint style