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arXiv · 1811.06520

Paper-boat relaxion

Shao-Jiang Wang
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Abstract

A new relaxion mechanism is proposed where a small electroweak scale is preferably selected earlier than the larger one due to a potential instability, which is different from previously proposed stopping mechanisms by either Hubble friction from an increasing periodic barrier or thermal friction from gauge boson production. The sub-Planckian field excursion of an axion can be achieved without violating the bound on the $e$-folding number from a quantum gravity perspective; and our relaxion can be identified as a QCD axion, preserving the Peccei-Quinn solution to the strong $CP$ problem as well as making up all the cold dark matter in our current Universe.

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Shao-Jiang Wang. 2018-11-15. Paper-boat relaxion. https://doi.org/10.1103/physrevd.99.095026

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