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arXiv · 1706.00438

Relaxed Inflation

Abstract

We present an effective model where the inflaton is a relaxion that scans the Higgs mass and sets it at the weak scale. The dynamics consist of a long epoch in which inflation is due to the shallow slope of the potential, followed by a few number of e-folds where slow-roll is maintained thanks to dissipation via non-perturbative gauge-boson production. The same gauge bosons give rise to a strong electric field that triggers the production of electron-positron pairs via the Schwinger mechanism. The subsequent thermalization of these particles provides a novel mechanism of reheating. The relaxation of the Higgs mass occurs after reheating, when the inflaton/relaxion stops on a local minimum of the potential. We argue that this scenario may evade phenomenological and astrophysical bounds while allowing for the cutoff of the effective model to be close to the Planck scale. This framework provides an intriguing connection between inflation and the hierarchy problem.

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BibTeXRIS

Walter Tangarife, Kohsaku Tobioka, Lorenzo Ubaldi, Tomer Volansky. 2017-06-01. Relaxed Inflation. https://arxiv.org/abs/1706.00438

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