Electron passing through two slits

Maybe it is possible to pinpoint the electron passing through two slits. Indeed, one may think of the Compton effect a photon collides with an electron and changes its direction, and this can be detected ( a flash on the electron"). When one prepares two such ambushes at the two open slits, it turns out that the flash is always on a single slit, not on both. This cannot be true ... 

We have to accept that the electron passes through two slits. This is a blow to those who believe in the reality of the world. Maybe it only pertains to the electron, maybe the Moon is something completely different A weak hope. The same thing... 

Figure 15.2 A Hypothetical Experiment with Electrons Passing through Two Slits.

Maybe it is possible to pinpoint the election passing through two slits Indeed, one may think of the Compton effect a photon collides with an electron, changes its direction and this can be detected ( a Bash on the electron ). When one prepares two such ambushes at the two open slits, it turns out that the flash is always on a single slit, not on both. This cannot be true K it were true, then the pattern would be of a NON-interference character (and had to be the sum of the two one-slit patterns), but we have the interference. No. There is no interference. Now, the pattern does not show the interference. The interference was when the electrons were not observed. When we observe them, there is no interference. Somehow we perturb the electron s momentum (the Heisenberg principle) and the interference disappears. 

When a beam of electrons goes through two closely spaced slits (a), an interference pattern is created, as if the electrons were waves. By contrast, a beam of particles passing through two slits (b) produces two smaller beams of particles. Notice that particle beams produce two bright stripes with darkness in between but waves produce the brightest strip directly in the center of the screen. 

Sketch the interference pattern that results from the diffraction of electrons passing through two closely spaced slits. 

A particle, photon or electron, passing through slit A and striking the detection screen at point x has wave function a( ), while a similar particle passing through slit B has wave function b( )- Since a particle is observed to retain its identity and not divide into smaller units, its wave function ft (x) is postulated to be the sum of the two possibilities... 

Figure 10. Two-slit diffraction experiment of the Aharonov-Bohm effect. Electrons are produced by a source at X, pass through the slits of a mask at Y1 and Y2, interact with the A field at locations I and II over lengths h and l2, respectively, and their diffraction pattern is detected at III. The solenoid magnet is between the slits and is directed out of the page. The different orientations of the external A field at the places of interaction I and II of the two paths 1 and 2 are indicated by arrows following the right-hand rule.

However, since one electron or proton has two possible spin states, N electrons or protons have 2N possible states (just like the coin toss case). Molecules can be configured to be simultaneously in many different quantum states, just as the electron in the two-slit experiment seems to pass through both slits simultaneously. In principle, this property can be used someday to make massively parallel computers, and such computers with five or six bits have been made in the laboratory (using NMR). As of this writing, nobody knows whether or not it will ever be possible to build a quantum computer which is big enough to do a computation faster than a conventional machine, although it is clear that NMR will not work for this application. 

In a two-slit experiment an electron wave passes through both slits to recombine, with interference, but without rupture. The interference pattern disappears on closure of one slit or when the slits are too far apart, compared to the de Broglie wavelength. It now behaves exactly hke a classical particle, when forced through a single slit (Holland, 1993). 

Clearly, the two parts of the electron united somehow and caused the flash at a single point on the screen. The quantum world is really puzzling. Despite the fact that the wave function is delocalized, the measurement gives its single point position (decoherence). How could an electron pass simultaneously through two slits We do not understand this, but this is what happens. 

For the two-slit experiment, according to standard QM, strict completion of Eq. (7) would make impossible to determine which hole the electron or photon passes through without, at the same time, disturbing the electrons or photons enough to destroy the interference pattern. This is a puzzling situation within the particle model. Somewhere, there is a missing link (see below). 

An UV light beam, obtained with an intensity-regulated deuterium lamp and a narrow-slit monochromator, passed through the gas phase between two perfectly aligned pin holes mounted in front of the optical windows. An EMR 541-N PM tube, with an appropriate interference filter placed immediately before it, was used in conjunction with associated electronics to continuously monitor the UV intensity as a means of measuring changes in concentration of the reagent gas. 

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