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CP violation
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Matter and antimatter behave slightly differently.
Matter and antimatter behave slightly differently in weak decays (kaons, B mesons), required to create more matter than antimatter. The observed amount is far too small to explain the universe.
Discovered in 1964.
Phase in the CKM matrix.
In more detail
CP violation is a small asymmetry in weak interactions where the laws are not symmetric under combined charge conjugation and parity. It was first observed in kaon decays.
Real-world uses
- CP violation is needed to explain the matter dominance of the universe.
- B-factories study CP violation in B mesons.
- Physicists study CP violation in kaon and B-meson decays, which helps explain why the universe contains matter.
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Frequently asked questions
Who discovered it?
Cronin and Fitch, in 1964, who received the 1980 Nobel Prize.
Why does it matter?
It helps explain why there is more matter than antimatter.
What does CP violation mean?
The laws of physics treat a particle and its mirror-image antiparticle slightly differently in certain decays.
Related topics in Particle Physics & Cosmology
Large Hadron Collider · Particle detectors · Neutrino oscillations · Matter–antimatter asymmetry · Grand unified theories · Supersymmetry