Two A5 modular symmetries for Golden Ratio 2 mixing

TL;DR

This paper proposes a novel leptonic mixing model utilizing two $A_5$ modular symmetries and two moduli, resulting in golden ratio mixing with perturbations, advancing modular flavor symmetry frameworks.

Contribution

It introduces a model with two $A_5$ modular symmetries and two moduli, providing a new approach to achieve golden ratio mixing in leptons.

Findings

Model reproduces golden ratio mixing pattern.

Residual symmetries depend on moduli stabilization.

Effective behavior mimics a single $A_5$ symmetry with two moduli.

Abstract

We present a model of leptonic mixing based on two $A_5$ modular symmetries using the Weinberg operator. The two modular symmetries are broken to the respective diagonal $A_5$ subgroup. At the effective level, the model behaves as a model with a single $A_5$ modular flavour symmetry, but with two moduli. Using both as stabilisers, different residual symmetries are preserved, leading to golden ratio mixing that is perturbed by a rotation.