Jul 3 – 8, 2016
The University of Melbourne
Australia/Melbourne timezone

Naturalness of the relaxion mechanism

Jul 7, 2016, 2:20 PM
Alice Hoy Room 242

Alice Hoy Room 242

Talk Non-SUSY and Exotics Non-SUSY and Exotics


Andrew Fowlie


The relaxion mechanism is a novel solution to the hierarchy problem that utilizes the dynamics of an axion-like field. I discuss results from the first statistical analysis of the relaxion mechanism (arXiv:1602.03889), in which we quantified the relative plausibility of a QCD and a non-QCD relaxion model versus the Standard Model with Bayesian statistics, which includes an automatic penalty for fine-tuning. We included experimental constraints upon the weak-scale, $\theta_\text{QCD}$ and inflationary observables measured by Planck/BICEP. Whilst we confirmed that relaxion models could solve the hierarchy problem, we found that their unconventional cosmology demolishes their plausibility.

Primary author

Andrew Fowlie


Csaba Balazs (Monash University) Graham White (Monash university) Luca Marzola (University Of Tartu) Martti Raidal (Nat. Inst. of Chem.Phys. & Biophys. (EE))

Presentation materials