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arXiv · 1101.0393

The Golden Ratio Prediction for the Solar Angle from a Natural Model with A5 Flavour Symmetry

Ferruccio Feruglio·Alessio Paris
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Abstract

We formulate a consistent model predicting, in the leading order approximation, maximal atmospheric mixing angle, vanishing reactor angle and tan {\theta}_12 = 1/{\phi} where {\phi} is the Golden Ratio. The model is based on the flavour symmetry A5 \times Z5 \times Z3, spontaneously broken by a set of flavon fields. By minimizing the scalar potential of the theory up to the next-to-leading order in the symmetry breaking parameter, we demonstrate that this mixing pattern is naturally achieved in a finite portion of the parameter space, through the vacuum alignment of the flavon fields. The leading order approximation is stable against higher-order corrections. We also compare our construction to other models based on discrete symmetry groups.

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Ferruccio Feruglio, Alessio Paris. 2011-01-02. The Golden Ratio Prediction for the Solar Angle from a Natural Model with A5 Flavour Symmetry. https://doi.org/10.1007/jhep03(2011)101

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