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arXiv · 0905.1514

Processing of Cosmological Perturbations in a Cyclic Cosmology

Robert H. Brandenberger
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Abstract

The evolution of the spectrum of cosmological fluctuations from one cycle to the next is studied. It is pointed out that each cycle leads to a reddening of the spectrum. This opens up new ways to generate a scale-invariant spectrum of curvature perturbations. The large increase in the amplitude of the fluctuations quickly leads to a breakdown of the linear theory. More generaly, we see that, after including linearized cosmological perturbations, a cyclic universe cannot be truly cyclic.

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Robert H. Brandenberger. 2009-05-10. Processing of Cosmological Perturbations in a Cyclic Cosmology. https://doi.org/10.1103/physrevd.80.023535

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