The Neutrino Revolution: Gravitational Collapse, the Origin of the Elements, and Dark Matter

George Fuller

If it were not for neutrinos you probably wouldn't exist! A surprising stattement given that neutrinos are electrically neutral, spin-1/2 particles that at best interact through the weak interaction (which is some twenty orders of magnitude weaker than electricity). Seventy-three years ago, W. Pauli proposed that particles like these accounted for the "missing energy" in nuclear beta decay and fretted that he had proposed the existence of a particle which could never be detected. Indeed, we have known very little about these particles until quite recently. But in the last few years there has been an experimentally- and observationally-driven revolution in fundamental neutrino physics/astrophysics. We now know the mass differences between these particles and how they "mix" across the families of elementary particles. There are even hints of the existence of more exotic kinds of neutrinos. And all of this has profound implications for our theories of the content and evolution of the cosmos. The weak interaction is at the root of why stars shine and explode. Neutrinos bring about the supernova explosions which follow gravitational collapse events. They also play a key role in the creation of the elements in the early universe and in supernova explosions and they comprise at least some of the Dark Matter.

The P/T Colloquium is
typically held each
Thursday, 3:45–5:00 PM.
Refreshments are served
at 3:15 PM.