Collapse or eternal expansion are the only 'asymptotic' destinies we know about from the study of the relevant equations that describe Big Bang cosmology. However, in some exotic cosmological models, it has been proposed that when our universe gets to be 'flat' enough, parts of space may suddenly bubble off to produce a baby universe as space-time becomes unstable. We do not really know enough about the dynamics of space-time to fully understand what may happen to it under all circumstances.