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arXiv · 1205.6637

Growth of covariant perturbations in the contracting phase of a bouncing universe

Atanu Kumar
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Abstract

In this paper we examine the validity of the linear perturbation theory near a bounce in the covariant analysis. Some linearity parameters are defined to set up conditions for a linear theory. Linear evolution of density perturbation and gravitational waves have been computed previously. We have calculated the vector and scalar induced parts of the shear tensor. For radiationlike and dustlike single fluid dominated collapsing Friedmann-Lemaitre-Robertson-Walker background it is shown that the linearity conditions are not satisfied near a bounce.

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Atanu Kumar. 2012-12-20. Growth of covariant perturbations in the contracting phase of a bouncing universe. https://doi.org/10.1103/physrevd.86.123522

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