A parameter-free prediction of the PMNS CP-violating phase is derived from the G₂ root system and the Fano plane PG (2, 2). The minimum root angle of G₂ is π/6 = 30°. The Fano plane contains 7 points. The prediction δCP = 7×30° = 210° lies within 0. 33σ of the experimental value 197°±40° (PDG 2024). At δCP = 210°, sin (210°) = −1/2 exactly, directly linking the CP phase to the baryon asymmetry of the Universe. The prediction will be decisively tested by Hyper-Kamiokande (2027–2030) with precision ~10°. Part of the OTIS series (DOI: 10. 5281/zenodo. 19160535).
Sergey Borisovich Zeksel (Sat,) studied this question.