Although cosmology is usually considered an observational science, where
there is little or no space for experimentation, other approaches can (and have
been) also considered. In particular, we can change rather drastically the
above, more passive, observational perspective and ask the following question:
could it be possible, and how, to create a universe in a laboratory? As a
matter of fact, this seems to be possible, according to at least two different
paradigms; both of them help to evade the consequences of singularity theorems.
In this contribution we will review some of these models and we will also
discuss possible extensions and generalizations, by paying a critical attention
to the still open issues as, for instance, the detectability of child universes
and the properties of quantum tunnelling processes.Comment: To appear in the proceedings of the "9th Workshop on what comes
beyond the standard model", Bled, Slovenia, September 16-26, 2006. LaTe
