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arXiv · hep-ph/0404289

Planck-Scale Effects on Global Symmetries: Cosmology of Pseudo-Goldstone Bosons

Eduard Masso·Francesc Rota·Gabriel Zsembinszki
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Abstract

We consider a model with a small explicit breaking of a global symmetry, as suggested by gravitational arguments. Our model has one scalar field transforming under a non-anomalous U(1) symmetry, and coupled lo matter and to gauge bosons. The spontaneous breaking of the explicitly broken symmetry gives rise to a massive pseudo-Goldstone boson. We analyze thermal and non-thermal production of this particle in the early universe, and perform a systematic study of astrophysical and cosmological constraints on its properties. We find that for very suppressed explicit breaking the pseudo-Goldstone boson is a cold dark matter candidate.

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Eduard Masso, Francesc Rota, Gabriel Zsembinszki. 2004-11-23. Planck-Scale Effects on Global Symmetries: Cosmology of Pseudo-Goldstone Bosons. https://doi.org/10.1103/physrevd.70.115009

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