Ultrahigh energy cosmic ray fluxes and cosmogenic neutrinos

We discuss the possible origin of the two neutrino shower events reported by the IceCube Collaboration at the Neutrino 2012 conference in Kyoto, Japan. The suspicion early on was that these two events are due to cosmogenic neutrinos and possibly by electron antineutrinos generating the Glashow resonance. The difference of the energy of the W− in the resonance and the energy estimates of the detected cascade events makes this assumption unlikely. The conclusion then may be that these high energy neutrinos are produced at sources of high energy cosmic rays such as Active Galactic Nuclei