## Abstract

We consider a nonsingular origin for the universe starting from an Einstein static universe in the framework of a theory which uses two volume elements √-gd ^{4}x and Φd ^{4}x, 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 nonsingular 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.

Original language | English |
---|---|

Pages (from-to) | 2767-2771 |

Number of pages | 5 |

Journal | International Journal of Modern Physics D |

Volume | 20 |

Issue number | 14 |

DOIs | |

State | Published - 31 Dec 2011 |

## Keywords

- Nonsingular cosmologies
- cosmological constant problem
- emergent universe scenarios
- two measures theories

## ASJC Scopus subject areas

- Mathematical Physics
- Astronomy and Astrophysics
- Space and Planetary Science