Strong cosmic censorship in polarised Gowdy spacetimes

The strong cosmic censorship conjecture says that 'most' spacetimes developed as solutions of Einstein's equations from prescribed initial data cannot be extended outside of their domains of dependence. Here, the authors discuss results which show that if they restrict attention to the polarised Gowdy spacetimes, strong cosmic censorship holds. More specifically, these results show that in the space of Cauchy data for polarised Gowdy spacetimes, there is an open dense subset for which the maximal globally hyperbolic development is inextendible. Among the Gowdy spacetimes which can be extended, the authors find a set of them which admit a countable infinity of inequivalent classes of extensions. They also find that a polarised Gowdy spacetime (T³ or S²*S¹) may be extended as a solution of Einstein's equations (with the Gowdy isometries) across a compact Cauchy horizon only if it is analytic.