engleski

A simple experimental checking of Heisenberg's uncertainty relations

We show that the quantum mechanical interpretation of diffraction of the light on a slit, where a wave function is assigned to a photon, can be used for a direct experimental studying of Heisenberg's position-momentum and equivalent position-wave vector uncertainty relation for the photon. Results of an experimental test of the position-wave vector uncertainty relation, where the wavelength is used as the input parameter, are given and they very well confirm our approach. The same experimental results can also be used for a test of the position-momentum uncertainty relation, when the momentum p0 of a photon is known as the input parameter. A measurement of p0, independent of the knowledge about the Planck's constant value, is proved to be possible. Using that value of p0, a test of the position-momentum uncertainty relation could be regarded as a method for a direct measurement of the Planck's constant. This is discussed, since the diffraction pattern is also well described by classical electrodynamics in experimental conditions considered. The given approach for testing Heisenberg's uncertainty relations is extremely simple and consequently suitable as a quantitative exercise in undergraduate experimental courses as well as a visual-attractive demonstration of the Heisenberg's uncertainty principle in courses of quantum mechanics.

Uncertainty relation; diffraction

nije evidentirano