How does wave-particle duality lead to the Heisenberg uncertainty principle?

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The Heisenberg uncertainty principle arises directly from the wave-particle duality of matter and radiation. Because subatomic entities exhibit both particle-like and wavelike characteristics, they do not possess a simultaneously precise position and momentum.12

The connection is rooted in the mathematical nature of waves:
* Position vs. Wavelength: A particle is most likely found where its associated wave is most intense. A wave that is strictly localized (precise position) must be composed of many wavelengths, making its overall wavelength—and thus its momentum—indeterminate.1
* Momentum vs. Spread: Conversely, a wave with a well-defined wavelength (precise momentum) is spread out over space, meaning the associated particle’s position is highly uncertain.1

Werner Heisenberg illustrated this using the thought experiment of observing an electron with a microscope. To locate the electron, one must bounce a photon off it. Using shorter wavelengths (higher energy) to improve position precision causes a greater, unpredictable recoil in the electron, thereby increasing the uncertainty in its momentum. This fundamental trade-off is a property of nature, not a limitation of measuring instruments.21