Implications for the Cosmic Ray Spectrum of a Negative Electron Neutrino   Mass^2
  The features and problems of a speculative model based on the electron neutrino being a tachyon are discussed. The model is consistent with five properties of the cosmic ray spectrum, and it predicts a flux of neutrons in a narrow energy region centered on 4.5 +/- 2.2 x 10^{15} eV. 
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