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arXiv · 1603.02606

Information Gain on Reheating: the One Bit Milestone

Jerome Martin·Christophe Ringeval·Vincent Vennin
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Abstract

We show that the Planck 2015 and BICEP2/KECK measurements of the Cosmic Microwave Background (CMB) anisotropies provide together an information gain of 0.82 +- 0.13 bits on the reheating history over all slow-roll single-field models of inflation. This corresponds to a 40% improvement compared to the Planck 2013 constraints on the reheating. Our method relies on an exhaustive CMB data analysis performed over nearly 200 models of inflation to derive the Kullback-Leibler entropy between the prior and the fully marginalized posterior of the reheating parameter. This number is a weighted average by the Bayesian evidence of each model to explain the data thereby ensuring its fairness and robustness.

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Jerome Martin, Christophe Ringeval, Vincent Vennin. 2016-03-08. Information Gain on Reheating: the One Bit Milestone. https://doi.org/10.1103/physrevd.93.103532

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