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arXiv · 1404.4080

Gowdy-symmetric cosmological models with Cauchy horizons ruled by non-closed null generators

Jörg Hennig
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Abstract

Smooth Gowdy-symmetric generalized Taub-NUT solutions are a class of inhomogeneous cosmological models with spatial three-sphere topology. They have a past Cauchy horizon with closed null-generators, and they are generally expected to develop a second Cauchy horizon in the future. Here we generalize these models to allow for past Cauchy horizons ruled by non-closed null generators. In particular, we show local and global existence of such a class of solutions with two functional degrees of freedom. This removes a periodicity condition for the asymptotic data at the past Cauchy horizon that was required before. Moreover, we derive a three-parametric family of exact solutions within that class and study some of its properties.

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Jörg Hennig. 2016-08-21. Gowdy-symmetric cosmological models with Cauchy horizons ruled by non-closed null generators. https://doi.org/10.1063/1.4961151

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