Comment on "The GSI method for studying neutrino mass differences - For   Pedestrians"
  It has been suggested that the reported temporal oscillations in the weak decay of H-like ions circulating in the GSI storage ring may be accounted for by interference between two different momentum components of the wave function of the parent ions. In that model, the interference is said to come about through coupling of those two momentum components to the two mass components in the wave function of the electron neutrino in the decayed state. I show here that quantum mechanics allows no such interference to contribute to the reported oscillation of the decay rate. The central issue is that the storage ring is a million times too small to allow the parent ion's wave function to produce the needed interference effect. This note supersedes earlier arXiv postings that were less general and less rigorous. 
Murray Peshkin