The idea that the Universe we observe today originated from an enormous
explosion (big bang) is now well known and widely accepted, at all
levels, in modern popular culture. But what happens to the Universe
before the big bang? And would it make any sense at all to ask such a
question? In fact, recent progress in theoretical physics, and in
particular in String Theory, suggests answers to the above questions,
providing us with mathematical tools able in principle to reconstruct
the history of the Universe even for times before the big bang. In the
emerging cosmological scenario the Universe, at the epoch of the big
bang, instead of being a "new born baby" was actually a rather "aged"
creature in the middle of its possibly infinitely enduring evolution.
The aim of this book is to convey this picture in non-technical language
accessible also to non-specialists. The author, himself a leading
cosmologist, draws attention to ongoing and future observations that
might reveal relics of an era before the big bang.