Cosmic Neutrinos

Understand

I recall the place of neutrinos in the electroweak theory and summarize what we know about neutrino mass and flavor change.

• I next review the essential characteristics expected for relic neutrinos and survey what we can say about the neutrino contribution to the dark matter of the Universe.
• Then I discuss the standard-model interactions of ultrahigh-energy neutrinos, paying attention to the consequences of neutrino oscillations, and illustrate a few topics of interest to neutrino observatories.
• I conclude with short comments on the remote possibility of detecting relic neutrinos through annihilations of ultrahigh-energy neutrinos at the $Z$ resonance.