TY - UNPB

T1 - Creating the Universe Without a Singularity and the Cosmological Constant Problem

AU - Guendelman, E. I.

PY - 2013

Y1 - 2013

N2 - We consider a non singular origin for the Universe starting from an Einstein static Universe in the framework of a theory which uses two volume elements √−gd4x and Φd4x, where Φ is a metric independent density, also curvature, curvature square terms, first order formalism and for scale invariance a dilaton field φ are considered in the action. In the Einstein frame we also add a cosmological term that parametrizes the zero point fluctuations. The resulting effective potential for the dilaton contains two flat regions, for φ → ∞ relevant for the non singular origin of the Universe and φ → −∞, describing our present Universe. Surprisingly, avoidance of singularities and stability as φ → ∞ imply a positive but small vacuum energy as φ → −∞. Zero vacuum energy density for the present universe is the ”threshold” for universe creation. This requires a modified emergent universe scenario, where the universe although very old, it does have a beginning.

AB - We consider a non singular origin for the Universe starting from an Einstein static Universe in the framework of a theory which uses two volume elements √−gd4x and Φd4x, where Φ is a metric independent density, also curvature, curvature square terms, first order formalism and for scale invariance a dilaton field φ are considered in the action. In the Einstein frame we also add a cosmological term that parametrizes the zero point fluctuations. The resulting effective potential for the dilaton contains two flat regions, for φ → ∞ relevant for the non singular origin of the Universe and φ → −∞, describing our present Universe. Surprisingly, avoidance of singularities and stability as φ → ∞ imply a positive but small vacuum energy as φ → −∞. Zero vacuum energy density for the present universe is the ”threshold” for universe creation. This requires a modified emergent universe scenario, where the universe although very old, it does have a beginning.

M3 - Preprint

BT - Creating the Universe Without a Singularity and the Cosmological Constant Problem

ER -