Nobel Prize Winner Lectures on 'Parity' In Initial Loeb Talk

Chen Ning Yang, professor of Physics at the Institute for Advanced Study at Princeton, described the events leading to his Nobel Prize-winning discovery of the non-conservation of parity at the first Morris Loeb Physics Lecture yesterday.

In his lecture, "The Role of Symmetry in Physics," Yang showed the relation between his discovery and parallel examples in physics where the discovery of "symmetry" and "invariance" in a system led to a law of conservation within the system. He cited conservation of linear momentum and the conservation of angular momentum as examples.

Yang theorized that if the definition of "parity" were extended to include the substitution of an "anti-particle" for a particle, in addition to the mirror image of the particle's physical position, symmetry would be conserved and the so-called law of parity would be valid. The experiment is not feasible, however, because not enough "anti-material" is obtainable, he said.

He will continue the series this Tuesday and Thursday with lectures on "The Weak Interactions" (molecular binding forces), and on Tuesday and Thursday of next week on "Many Body Problems."