Symmetries and Resonances

Abstract

The stimulus for my interest in the subject of symmetries and resonances was the series of lectures by Professor Salam at Trieste entitled “On Lie Groups and Lie Algebra.”¹ The theory of symmetries of elementary particle interactions has been revived by a completely new stimulus from the work of Gell-Mann² and Neéman,³ who recognized that the known eight baryons could be assumed to belong to the octet representation of the SU ₃ group. Once it is realized that it is the natural generalization of the isospin group to a higher dimension, it seems to be quite possible that various elementary particles and resonances can be classified under this scheme and also that very important relations like the Gell-Mann-Okubo⁴ formula, etc., can be derived. Therefore, I feel that any attempt to discuss such possibilities at this stage is justified.

The lecture is reproduced as it was prepared in January, 1962, before the discovery of the Ω -particle. Although it was possible to include new developments at the time of publication, these have been deliberately left out so as not to introduce “disharmony” in the presentation of matter which was based on the then-experimental situation.