Gowdy-Symmetric Vacuum and Electrovacuum Solutions

TL;DR

This paper presents new exact Gowdy-symmetric solutions in vacuum and electrovacuum spacetimes, exploring their properties, singularities, and causal structures, thereby advancing understanding of inhomogeneous cosmological models.

Contribution

It introduces families of exact solutions within Gowdy-symmetric models, including electrovacuum cases, and analyzes their singularity and horizon structures.

Findings

Solutions include Taub as a special case.

Certain parameter choices lead to curvature singularities.

Other choices yield singularity-free maximal regions.

Abstract

"Smooth Gowdy-symmetric generalized Taub-NUT solutions" are a class of inhomogeneous cosmological vacuum models with a past and a future Cauchy horizon. In this proceedings contribution, we present families of exact solutions within that class, which contain the Taub solution as a special case, and discuss their properties. In particular, we show that, for a special choice of the parameters, the solutions have a curvature singularity with directional behaviour. For other parameter choices, the maximal globally hyperbolic region is singularity-free. We also construct extensions through the Cauchy horizons and analyse the causal structure of the solutions. Finally, we discuss the generalization from vacuum to electrovacuum and present an exact family of solutions for that case.