double-slit experiment

In modern physics, the double-slit experiment demonstrates that light and matter can exhibit behavior associated with both classical particles and classical waves. This type of experiment was first described by Thomas Young in 1801 when making his case for the wave behavior of visible light. In 1927, Davisson and Germer and, independently, George Paget Thomson and his research student Alexander Reid demonstrated that electrons show the same behavior, which was later extended to atoms and molecules.

The experiment belongs to a general class of "double path" experiments, in which two diffracted waves reconverge, creating an interference pattern. Another version is the Mach–Zehnder interferometer, which splits the beam with a beam splitter.