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arXiv · 0901.1845

CMB anisotropies from acausal scaling seeds

Sandro Scodeller·Martin Kunz·Ruth Durrer
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Abstract

We investigate models where structure formation is initiated by scaling seeds: We consider rapidly expanding relativistic shells of energy and show that they can fit current CMB and large scale structure data if they expand with super-luminal velocities. These acausally expanding shells provide a viable alternative to inflation for cosmological structure formation with the same minimal number of parameters to characterize the initial fluctuations. Causally expanding shells alone cannot fit present data. Hybrid models where causal shells and inflation are mixed also provide good fits.

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Sandro Scodeller, Martin Kunz, Ruth Durrer. 2009-03-30. CMB anisotropies from acausal scaling seeds. https://doi.org/10.1103/physrevd.79.083515

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