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Mirror World and Axion: Relaxing Cosmological Bounds

Giannotti Maurizio
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Abstract

The cosmological (upper) limit on the Peccei-Quinn constant, related to the primordial oscillations of the axion field, can be relaxed for a mirror axion model. The simple reason is that the mirror world is colder and so the behavior of the axion temperature-dependent mass is dominated by the contribution from the mirror sector. So the coherent oscillations start earlier and correspondingly the axion mass density Ω_a h^2 is reduced.

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Giannotti Maurizio. 2005-04-28. Mirror World and Axion: Relaxing Cosmological Bounds. https://arxiv.org/abs/astro-ph/0504636

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