Gowdy Spacetimes

Gowdy Spacetimes have become useful test cases for studying the dynamics of Einstein's theory of General Relativity. Because they are simple enough to analyze and admit arbitrary wavelength gravitational waves, they provide insights into the full dynamics of general relativity that cannot be provided by homogeneous cosmological models. This review is intended as a basic conceptual introduction to these spacetimes. For a review that is oriented towards proving mathematical theorems about Gowdy spacetimes, see the Living Reviews in relativity article by Hans Ringström (http://www.livingreviews.org/lrr-2010-2, 2010) and the references cited there.