The positron: discovery of antimatter
El positrón: descubrimiento de la antimateria
- Date
- 1932 · confidence high
- Place
- Caltech, Pasadena, California, United States
- Credited to
- Carl Anderson
- Field
- Cosmos & Earth
What was discovered
In a cloud chamber with a magnetic field, Anderson photographs a particle with the mass of an electron and positive charge coming from cosmic rays: the antiparticle predicted by Dirac. Antimatter exists.
Blackett and Occhialini confirmed pair creation in Cambridge (1933); Anderson was unaware of Dirac's prediction.
What it led to
- Confirmation of Dirac's theory
- Physics of antiparticles (antiproton 1955, antihydrogen 1995)
- PET scanning
- Matter-antimatter asymmetry problem