Though the General Theory of Relativity has produced a generous amount of verified predictions,
its application to the universe at large has also generated a set of
puzzles which, coupled to recent observations, are the topics of intense
research. Whether there is a cosmological constant, whether the universe
is filled with dark matter and the nature of this stuff and whether our
current models of the universe are accurate enough to understand physics
to the very earliest of times are issues currently addressed by
researchers. The near future will provide more puzzles and some answers
leading us, we hope, to a better understanding of the universe, our
home.