Density growth in Kantowski-Sachs cosmologies with cosmological constant

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.

33 pages, 17 pictures

References in corpus (11)

• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• Quantum Nature of the Big Bang
• Matter Bounce Cosmology with the f(T) Gravity
• Relativistic cosmology and large-scale structure
• Black holes in three dimensional higher spin gravity: A review
• A covariant approach for perturbations of rotationally symmetric spacetimes
• Bianchi Model CMB Polarization and its Implications for CMB Anomalies
• Anisotropy in the Hubble constant as observed in the HST Extragalactic Distance Scale Key Project results
• Possible extensions of the standard cosmological model: anisotropy, rotation, and magnetic field
• Exact solutions in bouncing cosmology
• Density growth in Kantowski-Sachs cosmologies with cosmological constant

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• On the initial singularity in Kantowski-Sachs spacetime
• General Perfect Fluid Perturbations of Homogeneous and Orthogonal Locally Rotationally Symmetric Class II Cosmologies
• Spatially Homogeneous Universes with Late-Time Anisotropy
• On the Interaction Between Electromagnetic, Gravitational, and Plasma Related Perturbations on LRS Class II Spacetimes
• Skyrme Fluid in Anisotropic Universe
• Perturbations of Kantowski-Sachs models with a cosmological constant
• Density perturbation and cosmological evolution in the presence of magnetic field in $f(R)$ gravity models