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arXiv · 1009.3500

Dark Before Light: Testing the Cosmic Expansion History through the Cosmic Microwave Background

Eric V. Linder·Tristan L. Smith
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Abstract

The cosmic expansion history proceeds in broad terms from a radiation dominated epoch to matter domination to an accelerated, dark energy dominated epoch. We investigate whether intermittent periods of acceleration are possible in the early universe -- between Big Bang nucleosynthesis (BBN) and recombination and beyond. We establish that the standard picture is remarkably robust: observations of anisotropies in the cosmic microwave background exclude any extra period of accelerated expansion between 1 \leq z \lesssim 10^5 (corresponding to 5\times10^{-4}\ {\rm eV} \leq T \lesssim 25\ {\rm eV}).

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Eric V. Linder, Tristan L. Smith. 2010-09-17. Dark Before Light: Testing the Cosmic Expansion History through the Cosmic Microwave Background. https://doi.org/10.1088/1475-7516/2011/04/001

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