Speaker
Helmut Friedrich , Albert Einstein Institut
Abstract
There are available now substantial numbers of stability results on solutions to Einstein’s field equations that either start with singularities in the past or are future complete. Among the future complete solutions there are classes that admit smooth extensions of their conformal structure beyond time-like infinity so that the extension and the extended conformal factor define again a solution to Einstein’s field equation. With the presently accept view that a cosmos should start with some sort of a big bang, these solutions cannot be interpreted off-hand as beginnings of new cosmologies. In the talk I shall present some of the known smoothly extensible future complete solutions to Einstein’s equations and discuss the question what the future asymptotics of solutions might need to satisfy so that their extensions could be regarded as defining a beginning of new cosmologies.