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Re: The Double Slit Experiment and wave-particle duality.

Q1.1: Is this interpretation correct: When just one single particle (and no more) is sent through the two slits but is not measured, it shows interference as if a wave of particles, equal to every possible path that could be followed by that single particle, has also been sent through the slits. Once it is measured and we discover the actual path that the single particle took, then we can see that the implied wave amplitudes did somehow interfere with the single particle in its path of travel, and it changed direction to account for those supposed impacts.

Q1.2: How do we know the particle behaves as a wave if we cannot measure it without that measurement collapsing the wave information?

(original post included additional questions regards many world interpretation, and virtual reality theory but have been removed to adher to posting guidelines)

mdkb
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When just one single particle (and no more) is sent through the two slits but is not measured, it shows interference...

Quote of the comment from Bill Alsept:

One particle will not make an interference pattern. It can make one mark on the detector and that’s it. It takes many individual impacts to form a pattern.

Interestingly, the detector can be placed as closed to the slit as you want and the impact always will be a dot from the single photon. Being close enough you are able to observe through which slit the photon was slipping through.

Furthermore behind single sharp edges and even with single photons after a while one will observe an intensity distribution on a detector screen. So slits with its difference in the path length from the right edge and from the left edge are not necessary to form an intensity pattern.

There is another point one can state. Th intensity distribution is a stationary pattern on the screen. That is an astonishing fact because Young derived the wave characteristics of light from the interference pattern of two water waves:

enter image description here

This sketch shows one moment of the “living” pattern. In reality the points C and D are moving to the top and the points E and F are moving downwards. This behavior is not observed for the intensity pattern from light.

What you can conclude from these observations?

  1. As you state right ...

How do we know the particle behaves as a wave if we cannot measure it without that measurement collapsing the wave information?

... the wave character is an interpretation and could not be observed directly.

  1. The interaction between sharp edges and photons is not an object of consideration. All the more a quantized force field between the surface electrons from the sharp edge and the photons are not discussed.

  2. The above phenomena are proved. The conclusion in point 2 is not recognized.

HolgerFiedler
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  • @holgerfielder you wrote "In reality the points C and D are moving to the top and the points E and F are moving downwards. This behavior is not observed for the intensity pattern from light." ok so this is new information for me. Are you saying Young has described water waves in the image, but in fact the light wave is nothing like that? so the image isnt actually correct for the wave pattern, or it is correct but just odd ? – mdkb Apr 01 '18 at 01:27
  • (apologies I am struggling with markdown html in this stackexchange and got locked out of the last question with 5 minute limit on editing it)

    @holgerfiedler

    I do not understand what you mean by "sharp edges" and am not sure why they are relevant to my questions.

     – mdkb Apr 01 '18 at 01:36
  • @mdkb the edges are relevant because a double slit has four edges that the photons pass by at a very close proximity. This effects how the photons diffract around the edges. – Bill Alsept Apr 01 '18 at 03:29
  • mdkb on a sunny day look on your finger in front of a white wall, you’ll see dark and white fringes. They are blurry because of the influence of an extended interaction between photons and the thick edge. Furthermore the concentration of surface electrons on sharp edges is the important thing to get sharp intensity distributions on the observer screen. – HolgerFiedler Apr 01 '18 at 05:41
  • https://physics.stackexchange.com/questions/382773/corpuscular-theory-of-light-and-double-slit-experiment – HolgerFiedler Apr 01 '18 at 05:44
  • https://physics.stackexchange.com/questions/90646/what-is-the-relation-between-electromagnetic-wave-and-photon/253957#253957 – HolgerFiedler Apr 01 '18 at 06:04
  • so you and @BillAlsept are essentially suggesting that the influence of the sharp edges on the slits is what is creating the wave effect of the particles at the quantum level because electons are emitting photons and being diffracted by the slits design constraints.

    I havent seen this aspect mentioned in any of the articles I have read on double slit experiment though? wouldnt it be considered a failure of the system and the experiment considered a failure if this was the case since it is disturbing the results? and why has no one noticed this, if it is the case?

     – mdkb Apr 02 '18 at 00:50
  • @mdkb The edges do affect the photons. Just Google razor edge or sharp edge defraction. Billions of coherent photons (individual photons) can resemble a wave. There are no slit design constraints because diffraction will happen even with a single edge, it doesn’t need to be a slit or slits. Light diffracting around edges has been noticed before and the experiment does not fail because the results are a diffraction pattern. – Bill Alsept Apr 02 '18 at 04:28
  • mdkb How do you think what is more exciting, an unobservable interference phenomenon of a wave particle duality or a ‘simple’ interaction of photon and electron? Please bear in mind that the last is not recognized and it’s a private opinion. Otherwise in PSE it was not pronounced not one inconsistency in this thought. As necessary a chain of evidence is built and it should be easy to find the flaw. This was until now not the case. This you can easy prove. – HolgerFiedler Apr 02 '18 at 05:17
  • well I certainly agree it is a contender for an explanation or at least an influence on the experiment, would be good to see some experiments testing this aspect. – mdkb Apr 02 '18 at 07:14
  • mdkb Good Point. An electric potential on the edge should change the distance between the fringes on the screen. – HolgerFiedler Apr 02 '18 at 10:08
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"we discover the actual path that the single particle took"

It is in principle impossible to set up the experiment in such a way that it is known through which slit it goes without destroying the interference.

my2cts
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    Thanks @my2cts for your comment but as I understand it the experiment shared in the link below showed that it is possible to get that information using particle entanglement and a TEM10 laser setting and the which-path information was resolved without the wave collapsing. the pinned comment from blueyes at the bottom of the article goes further to explain how important this experiment is in showing that. https://arstechnica.com/science/2012/05/disentangling-the-wave-particle-duality-in-the-double-slit-experiment/ – mdkb Apr 01 '18 at 01:09
  • @mdkb in the experiment you are quoting it is that the boundary conditions remained unchanged as far as "photons scattering off two slits" .usually when the detecting method interferes with the boundary conditions. This is seen here https://phys.org/news/2011-01-which-way-detector-mystery-double-slit.html – anna v Apr 02 '18 at 04:44