Modular Flavor Symmetry for Lepton Textures

This paper explores a specific extension of the Standard Model using modular flavor symmetry (specifically S3) to explain lepton masses and mixing. The authors focus on constructing models near fixed points in the modular space, leveraging residual symmetries and non-holomorphic modular forms to generate Yukawa textures. The key advantage is the potential to build economical models without the need for flavon fields, a common feature in flavor models. The paper's significance lies in its exploration of a novel approach to flavor physics, potentially leading to testable predictions, particularly regarding neutrino mass ordering.