Numerical black hole interiors and string cosmology initial conditions

Recent work has proposed the principle of `asymptotic past triviality' tocharacterize the initial state in the pre-big bang scenario of stringcosmology, that it is a generic perturbative solution of the low-energyeffective action. Among the more generic sets of solutions which is simpleenough to investigate thoroughly, yet complex enough to exhibit interestingbehavior, is the gravity-dilaton system in spherical symmetry. Since, in theEinstein frame, this system reduces to a massless minimally coupled scalar,which has been target of a large body of previous investigation, we will drawon this and interpret it in the cosmological context. Since this scenarionecessarily involves the transition from weak field initial data into thestrong field regime, gravitational collapse, we have made numericalcomputations to answer some of the questions raised on the road to the proposalthat `the pre-big bang is as generic as gravitational collapse'.Comment: 35 pages, 11 figures. Updated reference