Oak Ridge National Laboratory

Physics Division

Physics Division Seminars

Physics Division Seminars bring us speakers on a variety of physics related subjects. Usually these are held in the Building 6008 large Conference Room, at 3:00 pm on the chosen day, but times and locations may vary. For more information, contact our seminar chairman,

Alfredo Galindo-Uribarri
Tel (Office): (865) 574-6124  (FAX): (865) 574-1268

Fri., June 20, 2008, at 3:00 p.m. (refreshments at 2:40 p.m.)

Neutrinos – Going to Extremes

J.F. Wilkerson, University of Washington, Seattle, WA
Building 6008 Conference Room

In the past decade our understanding of neutrinos and their role in the universe has undergone a remarkable transformation. We have discovered that neutrinos morph from one species to another as they journey through matter and space. And based on these observations we know that neutrinos are not massless particles, but have tiny masses, being at least 250,000 times lighter than electrons. Yet even with such diminutive masses, neutrinos play important roles in shaping the largest scales of the cosmos.

Today there is much that remains unknown about neutrino properties. What do neutrinos “weigh” — we still do not know their absolute masses. Are neutrinos and anti-neutrinos indistinguishable from one another (Majorana particles), indicating lepton number violation? Might neutrinos account for the matter – antimatter asymmetry observed in the universe? Future neutrino experiments aim to address these questions, but the extreme nature of neutrinos presents daunting experimental challenges. However the consequences from deciphering neutrino properties will be profound, guiding us to the formation of a new "standard model" of fundamental particle interactions, impacting our models of astrophysics and cosmology, and perhaps holding the key to understanding our existence.