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Wave–particle duality
Intermediate
Quantum objects show both wave and particle behaviours.
Quantum objects show wave behaviour (interference) in propagation and particle behaviour (localised detection) on measurement. Neither classical picture is complete.
Single photons build up an interference pattern one dot at a time.
Not a switch between two states.
In more detail
Wave-particle duality means that all quantum objects show both wave and particle behaviour, depending on how they are observed. Waves describe interference, and particles describe localised detection.
Real-world uses
- Electron microscopes, lasers and semiconductors all rely on wave-particle duality.
- Quantum technologies exploit both aspects.
- Engineers designing quantum devices must use models that include both wave and particle behaviour of electrons.
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Frequently asked questions
Is an electron a wave or a particle?
Neither in the everyday sense. It is a quantum object that shows both aspects in different experiments.
Does observation change the outcome?
In double-slit experiments, detecting which slit disrupts the interference pattern.
Which view is correct?
Neither alone. Quantum objects behave as waves when unobserved and produce particle-like detections when measured.
Related topics in Quantum Mechanics
Pair production · de Broglie hypothesis · Davisson–Germer experiment · Double slit with electrons · Heisenberg uncertainty principle · Energy–time uncertainty