IV.P127 — Spectral transition as mode-switching

Each hydrogen spectral transition |n_2,l_2,m_2> to |n_1,l_1,m_1> is a CR-address mode-switching event on T^2: the initial and final CR-address states have winding numbers compatible with the respective quantum numbers, and the emitted photon carries energy Delta E and angular momentum Delta l = +/-1.