The double-slit experiment is a well-known and extensively performed experiment in physics, not just a theoretical concept. It has been performed numerous times in various settings and has played a crucial role in understanding the wave-particle duality of quantum mechanics.
The experiment involves shining a beam of particles (such as electrons or photons) through two parallel slits in a barrier and observing the pattern that emerges on a screen placed behind the barrier. Surprisingly, when particles are sent through the double slits one at a time, they display an interference pattern on the screen, similar to what is observed when waves pass through two slits.
This phenomenon demonstrates that particles, despite their individual nature, exhibit wave-like properties and can interfere with themselves. It was one of the key experimental observations that led to the development of quantum mechanics.
The double-slit experiment has been performed with a wide range of particles, including electrons, photons, neutrons, and even larger molecules like fullerenes. Each successful replication of the experiment has consistently shown the same interference pattern, confirming the wave-particle duality of quantum objects.
The experiment continues to be a subject of ongoing research and exploration, as it provides insights into the fundamental nature of particles and the behavior of quantum systems.