The Endless Universe
Paul Steinhardt
Princeton University
Abstract
The conventional view is that the universe begins as
an infinitesimal point in a
bang and expands and cools forever. Its evolution is
marked by epochs of inflation, radiation- and matter-domination,
and, finally, accelerated expansion.
Recently, a radical alternative
has emerged
which challenges nearly every aspect of the standard picture.
In this ``cyclic universe," space and time are endless.
The universe undergoes periodic evolution from big bang
to big crunch every trillion years or so, and the key
events that shape our current universe take place before
the last bang.
This talk will introduce and contrast the two views of the
universe, showing how each can explain current observations
and pointing out how they may be distinguished.