V.D80 — Ring Homomorphism Phi_p,n

The ring homomorphism Phi_{p,n}: R_partial^(micro) -> R_partial^(meso) is the boundary-ring map Lift_D circ Scale_{Xi_tau^(NT)} circ Embed_{A->D}, connecting the proton-neutron mass split (micro vertex) to the TOV scale (meso vertex) through sector-coupling algebra.