On the quantum mechanics of neutrino oscillation

We try to understand and to develop some of the basic quantum mechanics of neutrino oscillation. First, we observe that measurements which identify the physical neutrino (mass eigenstate) involved in each event of an experiment destroy any oscillation pattern. We explain how these measurements do that. Then, we construct a wave-packet treatment of neutrino oscillation. We find that it gives the same results as the standard treatment. Next, we estimate the distance a beam must travel before its different physical neutrinos, which have different speeds, will stop interfering with each other. Finally, we consider the possibility of observing the difference in the arrival times of the various physical neutrinos at a given point.