One-loop superstring cosmology and the nonsingular universe

We study the cosmological implications of the one-loop terms in string expansion. In particular, we find nonsingular solutions which interpolate between a contracting universe and an expanding universe, and show that these solutions provide a mechanism for removing the initial conditions problem peculiar to spatially closed FRW cosmologies. In addition, we perform numerical calculations to show that the nonsingular cosmologies do not require a careful choice of initial conditions, and estimate the likely magnitude of higher order terms in string expansion.