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Grand unified theories
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Attempts to unify the strong and electroweak forces.
Attempt to merge strong, weak and EM forces into one at ~10¹⁶ GeV; predict proton decay (T½ > 10³⁴ yr, not seen) and magnetic monopoles.
SU(5) model.
Couplings nearly meet only with supersymmetry.
In more detail
Grand unified theories propose that the strong, weak and electromagnetic forces are unified at very high energies. They predict new particles and processes such as proton decay.
Real-world uses
- GUTs guide searches for proton decay in underground detectors.
- They motivate the study of early universe physics.
- Theoretical physicists study grand unified theories that might connect the strong and electroweak forces at very high energy.
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Frequently asked questions
Has proton decay been observed?
Not yet, though experiments have set lower limits on the proton lifetime.
What energy is needed for unification?
Around 10¹⁶ GeV, far beyond current accelerators.
Is grand unification proven?
No. It is a theoretical idea that makes testable predictions, such as proton decay, which have not yet been observed.
Related topics in Particle Physics & Cosmology
Neutrino oscillations · CP violation · Matter–antimatter asymmetry · Supersymmetry · String theory · Our Sun