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de Broglie hypothesis
Intermediate
Matter has wave properties.
λ = h/pAll matter has an associated wavelength λ = h/p. Electrons accelerated through 100 V have λ = 0.12 nm, similar to atomic spacings.
A 1 g bullet at 500 m/s: 1.3×10⁻³⁴ m, unobservable.
It's a probability wave, not a physical vibration.
In more detail
Louis de Broglie proposed that particles have wavelength λ = h/p, linking matter to waves. This idea extended wave-particle duality to electrons and atoms.
Real-world uses
- Electron microscopes use the short wavelengths of electrons for high resolution.
- Neutron diffraction uses de Broglie wavelengths to probe crystal structures.
- Electron microscopes use the de Broglie wavelength to achieve resolutions far finer than optical microscopes.
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Frequently asked questions
Are de Broglie waves physical?
They describe the wave behaviour of particles, confirmed by diffraction experiments.
Why don't everyday objects show wave behaviour?
Their wavelengths are far too small to measure.
Are electrons waves or particles?
Both. Their wave behaviour is seen in diffraction, while they are detected as individual particles.
Related topics in Quantum Mechanics
Photon momentum · Compton effect · Pair production · Davisson–Germer experiment · Wave–particle duality · Double slit with electrons