A Solution to the Graceful Exit Problem in Pre-Big Bang Cosmology

Abstract

We examine the string cosmology equations with a dilaton potential in the context of the Pre-Big Bang Scenario with the desired scale factor duality, and give a generic algorithm for obtaining solutions with appropriate evolutionary properties. This enables us to find pre-big bang type solutions with suitable dilaton behaviour that are regular at $t=0$, thereby solving the graceful exit problem. However to avoid fine tuning of initial data, an `exotic' equation of state is needed that relates the fluid properties to the dilaton field. We discuss why such an equation of state should be required for reliable dilaton behaviour at late times.

16 pages LaTeX, 5 figures. To appear in Physical Review D

References in corpus (3)

• Superstring Cosmology
• Reconstructing the Cosmic Equation of State from Supernova distances
• The graceful exit in pre-big bang string cosmology

Cited by in corpus (5)

• The Pre-Big Bang Scenario in String Cosmology
• Non-Abelian T-duality in Pre-Big-Bang Cosmology
• Rotation in string cosmology
• A model for time-dependent cosmological constant and its consistency with the present Friedmann universe
• Long-wavelength approximation for string cosmology with barotropic perfect fluid