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arXiv · 1106.4932

Density growth in Kantowski-Sachs cosmologies with cosmological constant

Michael Bradley·Peter K. S. Dunsby·Mats Forsberg·Zoltán Keresztes
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Abstract

In this work the growth of density perturbations in Kantowski-Sachs cosmologies with a positive cosmological constant is studied, using the 1+3 and 1+1+2 covariant formalisms. For each wave number we obtain a closed system for scalars formed from quantities that are zero on the background and hence are gauge-invariant. The solutions to this system are then analyzed both analytically and numerically. In particular the effects of anisotropy and the behaviour close to a bounce in the cosmic scale factor are considered. We find that typically the density gradient in the bouncing directions experiences a local maximum at or slightly after the bounce.

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Michael Bradley, Peter K. S. Dunsby, Mats Forsberg, Zoltán Keresztes. 2012-04-30. Density growth in Kantowski-Sachs cosmologies with cosmological constant. https://doi.org/10.1088/0264-9381%2F29%2F9%2F095023

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