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Electroweak unification
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Electromagnetic and weak forces unite at high energy.
At energies above ~100 GeV the electromagnetic and weak forces merge into one electroweak interaction (Glashow–Weinberg–Salam). The Higgs mechanism breaks the symmetry at lower energies.
Photon and Z are mixtures of the original fields.
Predicted W and Z masses.
In more detail
Electroweak unification combines electromagnetism and the weak interaction into a single theory at high energies. At low energies, the two forces appear different because of the Higgs mechanism.
Real-world uses
- Electroweak unification predicts the masses of the W and Z bosons.
- It was confirmed by experiments at CERN.
- Physicists use electroweak unification to predict the connection between electromagnetic and weak interactions at high energy.
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Frequently asked questions
Who developed the theory?
Glashow, Salam and Weinberg, who received the 1979 Nobel Prize.
What is the energy scale of unification?
Around 100 GeV, roughly the energy at which the W and Z masses appear.
Why are the two forces different at low energy?
The W and Z bosons are massive, which limits the weak force's range, while the photon is massless, giving electromagnetism a long range.
Related topics in Particle Physics & Cosmology
Asymptotic freedom · Confinement · Weak interaction · Conservation laws in particles · Feynman diagrams · Particle accelerators