I have heard many lectures claiming that even a single electron being shot toward the slits will eventually lead to construction of an interference pattern. The rationale for firing one electron at a time is that by using a single electron the possibility of the electron interacting/interfering with other electrons from the electron gun is eliminated. My question is this: The slot is composed of atoms which have electrons. So the fired electron can interfere or interact with anyone or more of the slit electrons thereby nullifying the logic of firing one electron at a time. How does the presence of the slot wall electrons or atoms affect the experiment?
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As far as I know there is no detailed model about the interaction between the incoming electron and the electrons/nuclei at the slits.
The so-called "classical" prediction for this experiment (two lines behind the slits) is NOT the prediction of the relevant classical theory (classical electromagnetism) but the prediction of Newtonian mechanics for neutral objects interacting only by direct collisions (Feynman's "bullets" example). It is an irrelevant example, as Newtonian mechanics of neutral objects cannot predict electromagnetic induction either.
It would be interesting to model this experiment in the form of charged bullets sent towards a barrier consisting of an equal number of positively and negatively charged bullets. I was unable to find such a treatment.
Andrei
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Whenever someone investigates the interaction between photons and edges, we interpret the fringes behind an edge as a manifestation of the wave character of the particles. And, at the same time, we always emphasise that these waves are not directly observable. It is therefore only one of the possible interpretations that from fringes with a wavelike intensity distribution behind an edge we can conclude about a wave-particle-duality.
How does the presence of the slot wall electrons or atoms affect the experiment?
The interpretation of the fringes as the result of the interaction between photons (or electrons) and the electric field of the electrons on the edge surface respectively of phonon induction is not common, but has a certain charm. It is no longer necessary to interpret an electron (or photon) interference with itself in single-particle experiments. No more sentences like "we can write it down mathematically, but we can't describe what happens".
The common field between photon and electrons is quantised and the fringes are the manifestation of this quantised field. This must be demonstrated, for example, by changing the electrical potential of the edges.
HolgerFiedler
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In a real experiment you will have to deal with the effect of charging, so grounded metal is used for the slit system. Any electron reaching the matter is removed.
https://www.hitachi.com/rd/research/materials/quantum/doubleslit/index.html https://www.jeol.com/words/emterms/20121023.070758.php#gsc.tab=0
No undisclosed interests ;-).
my2cts
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You are right that most explanations of the two-slits experiment treat the screen that surrounds the slits as a classical barrier, and neglect the interactions between the individual particles passing through the slits and the individual particles that comprise the screen. The justification is that the nature of those detailed interactions is not the cause of the diffraction pattern that is observed. You can perform experiments with neutrons or even quite large molecules and still get the same diffraction effect, so you can't explain it in terms of electromagnetic interactions with the individual particles comprising the screen.
Professor Sushing
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How does the presence of the slot wall electrons or atoms affect the experiment?
Answer: it makes no significant difference on the important outcome, which is: is there an interference pattern, or not?
As @Andrei correctly points out in his answer:
As far as I know there is no detailed model about the interaction between the incoming electron and the electrons/nuclei at the slits.
The reason is simple: covering one of the slits shouldn't make much difference if the physical edge of the slit was somehow contributing. And of course, there is absolutely no QM theory that would lead us to believe the edge itself interacts with a particle as it passes through the slit (and causing an interference pattern).
If you are willing to consider double slit experimental versions with photons (instead of unwieldy electrons) in one-at-a-time build-up: actual experiments show that the rule - as with electrons or any particle) is that it is the possible knowledge of which path information - and nothing else - that dictates. See the following experiment performed with polarizers in front of each slit, described in this paper. It is the relative orientation of the polarizers that control. If parallel, there is interference. If perpendicular, no interference. In each case, the same apparatus is present at each slit. So it can't have anything to do with a hypothetical interaction with the physical slit edge itself.
A relevant part of the paper, titled "Young's double-slit experiment with single photons and quantum eraser", says:
The which-path marker consists of two, mutually perpendicular, polarizing filters. With one oriented vertically and the other horizontally, they are butted together side-by-side and held in place using a standard lens holder.
Note that in this experiment, the parallel case is emulated by "erasing" the which path markers. The rule being: if it is possible, in principle, to determine which-path information, there will be no interference pattern. It does not matter whether the experimenter extracts that information from the setup, or not.
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The EM field encompasses the entire apparatus and beyond (all space), an excited electron in the electrode is already interacting thru the EM field with all the electrons in the apparatus .... even before emission! However in order to drive the electron to the detector/screen voltage potentials are used (charged slits and screen), the accelerated electron spends little time interacting with slit/apparatus electrons as the strong charges drive it into the screen (although some electrons are likely absorbed at the slit). Most electrons in the slit material are interacting with their nuclei, not so interested in the free electron, however metallic slit material which has free electrons can polarize the photons.
At the screen the very very small "interference" pattern is observed .... this due to the wavelike/resonant nature of the EM field. The EM field governs all interactions in our world/universe (except gravity and forces inside the nucleus), the screen electrons and the traveling electron must obey the EM field "rules" ... the EM field everywhere (even at the screen) was active even as the electron was being emitted ... more resonant pathways in the EM field are higher probability thus the pattern.
PhysicsDave
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