Density growth in Kantowski-Sachs cosmologies with a cosmological constant

Michael Bradley, Peter K S Dunsby, Mats Forsberg, Z. Keresztes

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

In this work, the growth of density perturbations in KantowskiSachs 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 analysed 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 direction experiences a local maximum at or slightly after the bounce.

Original languageEnglish
Article number095023
JournalClassical and Quantum Gravity
Volume29
Issue number9
DOIs
Publication statusPublished - May 7 2012

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scalars
perturbation
gradients
anisotropy

ASJC Scopus subject areas

  • Physics and Astronomy (miscellaneous)

Cite this

Density growth in Kantowski-Sachs cosmologies with a cosmological constant. / Bradley, Michael; Dunsby, Peter K S; Forsberg, Mats; Keresztes, Z.

In: Classical and Quantum Gravity, Vol. 29, No. 9, 095023, 07.05.2012.

Research output: Contribution to journalArticle

Bradley, Michael ; Dunsby, Peter K S ; Forsberg, Mats ; Keresztes, Z. / Density growth in Kantowski-Sachs cosmologies with a cosmological constant. In: Classical and Quantum Gravity. 2012 ; Vol. 29, No. 9.
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