On the impossibility to distinguish MSW transitions from vacuum oscillations for neutrino maximal mixing

Abstract

We show in a simple and general way that MSW resonant transitions for solar neutrinos are not observable in the case of maximal mixing among any number of neutrino generations.

Comments: RevTeX file, 4 pages. The postscript file is available at http://www.to.infn.it/teorici/giunti/papers.html Two misprints in Eq.(8) are corrected