Michael Shaevitz, Columbia University
Neutrino Masses and Oscillations: A View of the Next Steps

The past ten years have been a remarkable period for neutrino physics. Oscillations between different flavors of neutrinos have been established with two different mass differences and possibly a third. Contrary to theoretical expectations and in contrast to the quark mixing matrix, the mixing angles turn out to be very large for the observed atmospheric and solar oscillations. In addition, the data may be pointing us towards new types of sterile neutrinos. The current accelerator neutrino
program will sharpen up the measurement of many of the mass and mixing parameters as well as address the sterile neutrino question.

In this talk, this current program will be described and the future experimental possibilities to take the next step will be considered. Experiments using reactor neutrinos appear to be a key component for the future program along with long-baseline accelerator neutrino experiments. If nature cooperates, the stage could be set for discovering CP violation in neutrino mixings, a phenomena possibly related to the baryon asymmetry in the universe. Of course, neutrinos could, as in the past, continue to surprise us with even more unexpected properties.