Speaker
Description
The notion of weak isospin is usually associated with the birth of the standard model during the Sixties of the last century. However the idea of attributing to leptons a symmetry and quantum numbers analogous to isospin is much older, and the first instance of this idea can be found in a paper published in Nuovo Cimento in 1953 by Marcello Cini and Agusto Gamba. We discuss the most interesting aspects of that paper, highlighting some deep intuition present in their work.
We analyze the small number of articles citing Cini and Gamba, and explain the reasons why their contribution was criticized and quickly forgotten, essentially because the almost contemporary discovery of strangeness seemed to prove the inconsistency of their scheme, and only the much later introduction of the Cabibbo angle and the discovery of charm led to a modelization of weak isospin that is in many important aspects coherent with the original intuitions of 1953.
