ACCELERATION OF THE UNIVERSE DRIVEN BY THE CASIMIR FORCE

Abstract

We investigate an evolutional scenario of the FRW universe with the Casimir energy scaling like (-)(1 + z)4. The Casimir effect is used to explain the vacuum energy differences (its value measured in astrophysics is very small compared to the value obtained from quantum-field-theory calculations). The dynamics of the FRW model is represented in terms of a two-dimensional dynamical system to show all evolutional paths of this model in the phase space for all admissible initial conditions. We find also an exact solution for nonflat evolutional paths of the Universe driven by the Casimir effect. The main difference between the FRW model with the Casimir force and the ΛCDM model is that their generic solutions are a set of evolutional paths with a bounce solution and an initial singularity, respectively. The evolutional scenario is tested by using the SNIa data, FRIIb radiogalaxies, baryon oscillation peak and CMB observation. We compare the power of explanation of the model considered and the ΛCDM model using the Bayesian information criterion and the Bayesian factor. Our investigation of the information criteria of model selection showed preference for the ΛCDM model over other models considered. However, the presence of the negative-like radiation term can remove a tension between the theoretical and the observed primordial4He and D abundance.