Creating the Universe Without a Singularity and the Cosmological Constant Problem

Abstract

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 $\sqrt{-g}{d}^{4}x$ and $\Phi d^{4}x$, where $\Phi$ is a metric independent density, also curvature, curvature square terms, first order formalism and for scale invariance a dilaton field $\varphi$ 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 $\varphi \to \infty$ relevant for the non singular origin of the Universe and $\varphi \to -\infty$, describing our present Universe. Surprisingly, avoidance of singularities and stability as $\varphi \to \infty$ imply a positive but small vacuum energy as $\varphi \to -\infty$. 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.

Appeared in Proceedings to the 14th Workshop 'What Comes Beyond the Standard Models', 11. - 21. July 2011 Bled, DMFA-Zaloznistvo, Ljubljana, December 2011

References in corpus (2)

• Collapse of simple harmonic universe
• Emergent Universe from Scale Invariant Two Measures Theory