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How does the double-slit experiment demonstrate the wave-particle duality of matter?
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quantum mechanics
Brian Greene discusses the key formula in the photoelectric effect, an insight that helped launch the quantum revolution. This video is an episode in his Daily Equation series.
The double-slit experiment demonstrates wave-particle duality by showing that entities like electrons exhibit both wave-like and particle-like behaviors. When electrons are fired at a double-slit apparatus, they create an interference pattern, which is characteristic of waves passing through both slits simultaneously. However, each electron is detected as a single, localized particle at a specific point on the screen. This suggests that while the electron's probability of reaching a certain point is governed by wave mechanics, its detection is a discrete, particle-like event. This duality means that an electron is neither purely a wave nor purely a particle but exhibits properties of both depending on how it is measured.123