String-dominated cosmology

If string theory controls physics at the string scale, the dynamics of the early Universe before the GUT era will be governed by the low-energy string equations of motion. Studying these equations, we find that depending on the initial conditions when the stringy era starts, and on the time when this era ends, there are a variety of qualitatively distinct types of evolution. Among these is the possibility that the Universe underwent a period of inflation. A by-product of this analysis is the observation that it is often possible to erase any evidence of a dilaton at late times.