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Hidden sector axions: physics and cosmology

Hans Peter Nilles
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Abstract

Embedding hidden sector supergravity models in the framework of string theory leads to the appearance of axion-like degrees of freedom. Among them is the model independent axion of heterotic string theory. It has a decay constant of order of the Planck scale and could play the role of a quintessence field. In models allowing for the required $μ$ term in the TeV range, the hidden sector dynamics leads to a vacuum energy of $(0.003 {\rm eV})^4$ via a multiple see-saw effect. A solution to the strong CP-problem is provided by an additional hidden sector pseudoscalar with properties that make it an acceptable candidate for cold dark matter of the universe.

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Hans Peter Nilles. 2003-07-25. Hidden sector axions: physics and cosmology. https://arxiv.org/abs/hep-ph/0307312

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