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Weak interaction
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Responsible for beta decay and neutrino interactions.
Mediated by W and Z bosons; changes quark flavour, causes beta decay, and acts on all fermions. It violates parity maximally.
Neutron decay n → p + e⁻ + ν̄ₑ.
Responsible for fusion in the Sun's first step.
In more detail
The weak interaction is responsible for radioactive beta decay and some particle decays. It changes the flavour of quarks and leptons through the W and Z bosons.
Real-world uses
- Beta decay powers medical isotopes and carbon dating.
- Weak interactions are essential for the fusion in stars.
- Engineers and physicists study the weak interaction to understand beta decay in radioactive materials and in stars.
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Frequently asked questions
Why is it called weak?
Because its strength is much lower than electromagnetism at everyday energies.
What bosons carry it?
The W and Z bosons.
Why is it called the weak force?
It is far weaker than electromagnetism and the strong force at everyday energies, and it acts over a very short range.
Related topics in Particle Physics & Cosmology
Colour charge and QCD · Asymptotic freedom · Confinement · Electroweak unification · Conservation laws in particles · Feynman diagrams