V.R299 — Scope of the delta_A prediction

The proton-neutron mass difference prediction delta_A/m_n approx (sqrt(3)/2) iota_tau^6 is conjectural: the exponent 6 is identified from spectral-gap hierarchy but not yet derived from a complete breathing-mode analysis. Upgrading to tau-effective requires computing the isospin-splitting mode on T^2 explicitly. All three sqrt(3) predictions are correlated.