The double-slit experiment ( and its variations ), conducted with individual particles, has become a classic thought experiment for its clarity in expressing the central puzzles of quantum mechanics.

A low-intensity double-slit experiment was first performed by G. Taylor in 1909, by reducing the level of incident light until photon emission / absorption events were mostly nonoverlapping.

A double-slit experiment was not performed with anything other than light until 1961, when Clauss Jönsson of the University of Tübingen performed it with electrons.

In 2002, Jönsson's double-slit experiment was voted " the most beautiful experiment " by readers of Physics World.

The delayed-choice experiment and the quantum eraser are sophisticated variations of the double-slit with particle detectors placed not at the slits but elsewhere in the apparatus.

In the double-slit experiment, the two slits are illuminated by a single laser beam.

Like the Schrödinger's cat thought experiment, the double-slit experiment is often used to highlight the differences and similarities between the various interpretations of quantum mechanics.

The differences in the cumulative action along the different paths ( and thus the relative phases of the contributions ) produces the interference pattern observed by the double-slit experiment.

According to the relational interpretation of quantum mechanics, first proposed by Carlo Rovelli, observations such as those in the double-slit experiment result specifically from the interaction between the observer ( measuring device ) and the object being observed ( physically interacted with ), not any absolute property possessed by the object.

* Photon dynamics in the double-slit experiment

simple: Young's double-slit experiment

* Photon dynamics in the double-slit experiment

* Photon dynamics in the double-slit experiment

The notion of path difference and constructive or destructive interference used above for the double-slit experiment applies as well to the display of a single slit of light intercepted on a screen.

showed that we can use macroscopic oil droplets on a vibrating surface as a model of wave – particle duality — localized droplet creates periodical waves around and interaction with them leads to quantum-like phenomena: interference in double-slit experiment, unpredictable tunneling ( depending in complicated way on practically hidden state of field ) and orbit quantization ( that particle has to ' find a resonance ' with field perturbations it creates — after one orbit, its internal phase has to return to the initial state ).

At the beginning of the 19th century it became more and more evident that light does not simply propagate along straight lines ( Thomas Young published his double-slit experiment in 1807 ).

With the Young's interference experiment, or double-slit experiment, he demonstrated interference in the context of light as a wave.

The double-slit experiment is an illustration of wave-particle duality.

The resulting Huygens – Fresnel principle was extremely successful at reproducing light's behavior and, subsequently supported by Thomas Young's discovery of double-slit interference, was the beginning of the end for the particle light camp.

Coherence was originally conceived in connection with Thomas Young's double-slit experiment in optics but is now used in any field that involves waves, such as acoustics, electrical engineering, neuroscience, and quantum mechanics.

Afshar's experiment uses a variant of Thomas Young's classic double-slit experiment to create interference patterns to investigate complementarity.

The Englert – Greenberger duality relation provides a detailed treatment of the mathematics of double-slit interference in the context of quantum mechanics.

It was shown experimentally in 1972 that in a double-slit system where only one slit was open at any time, interference was nonetheless observed provided the path difference was such that the detected photon could have come from either slit.

* Movie showing single electron events build up to form an interference pattern in double-slit experiments.

The double-slit experiments showed that when light is sent through a grid, a characteristic interference pattern is observed, very similar to the pattern resulting from the interference of water waves ; the wavelength of light can be computed from such patterns.

It is evident from this double-slit experiment with an ensemble of individual electrons that, since the quantum mechanical wave function ( absolutely squared ) describes the completed interference pattern, it must describe an ensemble.

An example of a directly observable effect of superposition is interference peaks from an electron wave in a double-slit experiment.

In fact, quantum superposition results in many directly observable effects, such as interference peaks from an electron wave in a double-slit experiment.

The decohered elements of the system no longer exhibit quantum interference between each other, as in a double-slit experiment.

Schematic of double-slit experiment in which Aharonov – Bohm effect can be observed: electrons pass through two slits, interfering at an observation screen, with the interference pattern shifted when a magnetic field B is turned on in the cylindrical solenoid.

For example, if the double-slit experiment is performed with electrons, then a wave-like interference pattern is observed.

Schematic of double-slit experiment in which Aharonov – Bohm effect can be observed: electrons pass through two slits, interfering at an observation screen, with the interference pattern shifted when a magnetic field B is turned on in the cylindrical solenoid, marked in blue on the diagram.

The interference pattern generated by sending a beam of light through two parallel slits forms a network of linearly diverging fringes that seem to originate from the plane of the two slits ( see double-slit experiment ).

In his most recent publication, in 2005, he was able to qualitatively reproduce the interference pattern observed in electron double-slit experiments.

Visibility is similarly defined in double-slit interference.

Photons, atoms, electrons, neutrons, and molecules have exhibited interference in double-slit interferometers.

Measurement can interact with the system state in somewhat peculiar ways, as is illustrated by the double-slit experiment.

However, since the Schrödinger equation is a wave equation, a single particle fired through a double-slit does show this same pattern ( figure on left ).

Thus, in this theory electrons are quite clearly particles -- when a double-slit experiment is performed, its trajectory goes through one slit rather than the other.

This is the relevant type of coherence for the Young ’ s double-slit interferometer.

For example, in the classic double-slit experiment where electrons are fired randomly at two slits, an intuitive interpretation is that, where is the probability of that event.

The classic example of complementarity is illustrated by the double-slit experiment in which a photon can be made to exhibit particle-like properties or wave-like properties, depending on the experimental setup used to detect its presence.

This is similar to traditional double-slit and mirror interferometer experiments where the slits ( or mirrors ) can be arbitrarily far apart.