Abstract

With decades worth of data from high precision experiments and robust confirmation at the LHC , addressing the Standard Model flavor puzzle is more pressing than ever. I will pedagogically introduce the flavor puzzle, then demonstrate how understanding the origin of charge-parity (CP) violation offers a new starting point to address it. Group theoretically, the physical CP transformation of the Standard Model is a special outer automorphism (“symmetry of a symmetry”) of the theory and I will explain what that means in simple terms. Having this understood, it follows that certain classes of symmetries preclude the existence of CP transformations altogether, in which case matter-antimatter symmetry is violated by calculable (“geometrical”) phases. Interestingly, this mechanism of predictive CP violation is naturally present in UV completions of the Standard Model offered by String Theory. In such a UV complete approach to flavor, the existence of flavor symmetries beyond the Standard Model is imperative and understanding their outer automorphisms uncovers an auspicious unification of “traditional” flavor symmetries, modular symmetries, discrete R symmetries of supersymmetry, as well as CP symmetry – altogether dubbed the eclectic flavor symmetry. I will show a first explicit example model derived along these lines which can successfully accommodate the available experimental data, while giving rise to testable predictions for so-far undetermined parameters.