Anything Else?
Anti-matter
- Paul Dirac (1927) made the first successful combination of relativity & quantum mechanics. Predicted that for every particle there is an an anti-particle
- In 1933, Anderson used a cloud chamber to study the naturally occurring cosmic rays. Discovered the “positron”, the anti-particle of the electron.
- Now other antiparticles are known: anti-protons, ….
More
- In 1937, Anderson & Neddermeyer discovered another new kind of particle in cosmic rays. This particle, now called the muon, like an electron, but heavier.
- Then the pion, which decayed into a muon plus another particle (neutrino) assumed to exist to conserve energy. Neutrino interactions were not seen until 1962.