wavicle: an old topic

Mar 2019
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"...Typically the photons in the two slit experiment are not being measured as to which slit the photon goes through."
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@dragon:
What does this mean? People do not put a detector on the slits to track which slit the photon goes through for the sake of saving money, or they did it and got nothing different?
 

topsquark

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On the dance floor, baby!
"...Typically the photons in the two slit experiment are not being measured as to which slit the photon goes through."
...............................................
@dragon:
What does this mean? People do not put a detector on the slits to track which slit the photon goes through for the sake of saving money, or they did it and got nothing different?
Well, now that I think of it, detecting the photon without stopping the thing would probably be pretty hard. But if you can do it then there would be no diffraction pattern on the screen. That comes out of basic QM and I haven't ever heard of an exception to it.

-Dan
 
Jun 2016
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There have been experiments that show that the interference pattern requires there to be more than one possible route through the apparatus.
If the route is defined (e.g. by measuring which slit the particle passes through) the interference disappears.
If there are more than one possible route through the apparatus, it seems that the particle (electron, photon, etc) will take all possible routes
the different probabilities of the different routes will be reflected in the eventual interference pattern.
 
Mar 2019
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@dragon:

I think the physical interaction due to the existence of the detectors affects the behavior of electron. Photon is not exception too. To probe which slit the photon passes through itself is an interesting affair even people have to stop it (with detector).

In cases of no existence of detectors, the situation / course of the formation of the diffraction / interference pattern for electron is not the same as that for photon. This is an important thing. Theoretically primary analysis in a previous post (the analysis of wave speed of probability wave) also discloses the subtle difference of the wavicle property between electron and photon too.

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“There have been experiments that show that the interference pattern requires there to be more than one possible route through the apparatus.
If the route is defined (e.g. by measuring which slit the particle passes through) the interference disappears.
If there are more than one possible route through the apparatus, it seems that the particle (electron, photon, etc) will take all possible routes
the different probabilities of the different routes will be reflected in the eventual interference pattern.”

@ Woody:

I remember that once upon a time I had similar opinion in aknight’s thread too. Recently I think quite a lot about this and found some fishy (suspectable) points:

  1. In the old style CRT TV set, electron beam seems not willing to take another possible route on the grass screen. Why electron has to actively seek another slit on the apparatus to go through?
  2. From the angle of wave characteristic, it seems easy to understand that the electron will take all possible routes. But from the angle of particle characteristic, it’s weird that an object can pass through more than one slits. Even a mass point is hard to do it. The sea wave passes through the slits while the sand is blocked outside? What a joke. Wave and particle should be integral (wavicle).
  3. If the route is defined (the electron passes through either one of the slits) there should be “diffraction” pattern too (single slit experiment) although there will be no “interference” pattern. It’s obviously that the physical interaction of the detector disturbs the wave characteristic.
So, now I doubt if we are used to take inertial / habitual thought as truth…I doubt if there should be an alternative scenario to explain the double slits experiment.
 

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Jun 2016
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now I doubt if we are used to take inertial / habitual thought as truth
This is the base issue with QM
We are forced to admit that our habitual ways of looking at the world are fundamentally wrong.
On a macroscopic level, the probability of things happening as we habitually assume they should is so close to 100% that it is not a consideration.
However at microscopic levels, we find that the probabilities are no longer 100%
and that "reality" actually follows all possible probabilities.

If we fix one possibility at 100% (by for example putting a detector on one route) then the probability interference vanishes.
 
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Mar 2019
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@ Woody:
What I mean is that once upon a time when we saw two slits, we perhaps habitually considered that it's surely a "double slits interference pattern".
 

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topsquark

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Apr 2008
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On the dance floor, baby!
@ Woody:
What I mean is that once upon a time when we saw two slits, we perhaps habitually considered that it's surely a "double slits interference pattern".
That was before we knew that light could act both as a particle and a wave. What's really freaky is that when we try to observe light as a particle (in the, say, photo-electric effect) we get a particle...when we try to observe light as a wave (in the, say, diffraction pattern) we get a wave.

-Dan
 
Mar 2019
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"...What's really freaky is that when we try to observe light as a particle (in the, say, photo-electric effect) we get a particle...when we try to observe light as a wave (in the, say, diffraction pattern) we get a wave."
@ dragon:
Of course, Dandan. That's why I said in a previous post that "To probe which slit the photon passes through itself is an interesting affair even people have to stop it (with detector)."
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But according to the context, seems that I am talking electron with Woody...
How can we judge that it's surely a "double slits interference pattern" rather than the duplication of two "diffraction patterns"? (in the case of no detectors).
 

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