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A Model of Anthropic Reasoning, Addressing the Dark to Ordinary Matter Coincidence

Frank Wilczek
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Abstract

If inflation occurs after the breaking of Peccei-Quinn symmetry then large values of the breaking scale $F$, which are forbidden in conventional axion cosmology, are permitted, provided that we inhabit a region of the Multiverse where the initial misalignment is small. Regions having approximately this initial misalignment may occupy a small volume of the Multiverse, but they contain a large fraction of potential observers. This scenario has many consequences, including a possible explanation of the approximate equality of dark and baryon matter densities.

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Frank Wilczek. 2004-09-17. A Model of Anthropic Reasoning, Addressing the Dark to Ordinary Matter Coincidence. https://arxiv.org/abs/hep-ph/0408167

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