The Leptonic CP Phase Is 0 or π Because the C60 Adjacency Is Real

The adjacency matrix of the C60 cage is real. A real matrix equals its own transpose, so the mixing operator built from it satisfies T-dagger = T-transpose, and a mixing operator that equals its own transpose cannot carry a complex phase. The leptonic CP phase is therefore pinned to 0 or π. This is a theorem, not a fit. A small leakage from the family lag widens the prediction from the two exact points to a narrow band, π ± 6.3 degrees at the present flow position. The current global best fit for the phase sits on π, within one sigma. The framework takes the opposite side from maximal CP violation: a phase resolved away from 0 and π, beyond the leakage band, ends the result. The experiments that decide it are the long-baseline neutrino programs.