Next: Feynman Diagrams Up: SMALL STUFF Previous: SMALL STUFF


High Energy Physics

Before we begin to construct a classification scheme for the ``elementary'' particles, we need to have some feeling for the phenomenology involved --- and maybe even a bit of historical perspective.

In some sense high energy physics (the experimental discipline) began when the first cyclotron capable of producing pions ``artificially'' was built by Ernest Orlando Lawrence at Berkeley in the early 1940's.gif However, high energy physics (the behaviour of Nature) began in the instant of creation of the Universe --- and it will be a long time before we are able to study the interactions of matter at the energies and densities of those first few femtoseconds.gif I will compromise by dating high energy physics (the modern human endeavour) from the hypothesis of Hideki Yukawa in 1935 that the strong nuclear force must be mediated by the exchange of particles of intermediate [between electrons and protons] mass, which he therefore named `` mesons'' [as in mesozoic or Mesopotamia(?)]. Where did he ever get such an idea?