Classical resolution of singularities in dilaton cosmologies

Abstract

For models of dilaton-gravity with a possible exponential potential, such as the tensor-scalar sector of IIA supergravity, we show how cosmological solutions correspond to trajectories in a 2D Milne space (parametrized by the dilaton and the scale factor). Cosmological singularities correspond to points at which a trajectory meets the Milne horizon, but the trajectories can be smoothly continued through the horizon to an instanton solution of the Euclidean theory. We find some exact cosmology/instanton solutions that lift to black holes in one higher dimension. For one such solution, the singularities of a big crunch to big bang transition mediated by an instanton phase lift to the black hole and cosmological horizons of de Sitter Schwarzschild spacetimes.

24 pages, 2 figures

References in corpus (6)

• Higher-dimensional resolution of dilatonic black hole singularities
• Exact solution of scalar field cosmology with exponential potentials and transient acceleration
• String--Kaluza--Klein Cosmology
• Cosmology as Relativistic Particle Mechanics: From Big Crunch to Big Bang
• Cyclical Behaviour in Early Universe Cosmologies
• Cosmological D-instantons and Cyclic Universes

Cited by in corpus (7)

• Dynamical compactification from de Sitter space
• Non-Extremal D-instantons and the AdS/CFT Correspondence
• Static dilatonic black hole with nonlinear Maxwell and Yang-Mills fields of power-law type
• Simple model of big-crunch/big-bang transition
• Probing the cosmological singularity with a particle
• Space-time filling branes in non critical (super) string theories
• From Wave Geometry to Fake Supergravity