Perturbations of Kantowski-Sachs models
arXiv:1303.4576
Abstract
Perturbations of Kantowski-Sachs models with a positive cosmological constant are considered in a harmonic decomposition, in the framework of gauge invariant 1+3 and 1+1+2 covariant splits of spacetime. Scalar, vector and tensor modes are allowed, however they remain vorticity-free and of perfect fluid type. The dynamics is encompassed in six evolution equations for six harmonic coefficients.
3 pages, to be published in the Proceedings of the Thirteenth Marcel Grossmann Meeting, Stockholm, Sweden 2012