Second generation leptons muon & tau as quantum excitiation of electrons? We know that in the hydrogen atom, the levels of the electron are quantized n=1, n=2, n=3 which can explain the ryderg constant and photon emission spectrum. the electron can be explained by a quantum wave function, and excited to higher levels, which when falls back to ground state, gives off photons of specific frequency. Could the second and third generation lepton, the muon and tao lepton be formulated, with assistance of the koide mass formula, as some kind of excitation of the electron? Does string theory for example able to model the muo and tau as n=2 and n=3, which decomposes to ground state, giving off other particles? What about preon theory? In other words, in string theory, does the electron represent a stable ground state of the lepton, and the second and third generation represent quantized excitation of this ground state, which is why they are unstable? what about preon theory? in addition to leptons, what about quarks.