Double slit mystery in relation to holography and the single slit?

[PeterDonis]

he was saying the 'classical' electromagnetic wave of a single photon was traveling through both slits and causing the interference. If this was the case(assume a 19 century knowledge and setup - prior to qm), one would probably expect interference effects from a single photon on the plate(provided the electromagnetic wave spread is bigger than the distance between the slits).

There is no such thing as "a single photon" in classical EM. In classical EM, as I said in post #34, no matter how faint you make the light source, you never get dots on the detector screen. Also, if you put something that detects the passage of light at the slits, classical EM predicts it will register light passing continuously at both slits, not discrete "photon" events at one slit or the other.

So to say that classical EM would lead you to expect "interference effects from a single photon" is not even wrong. What you say at the end of your post...

he seemed intent on using classical electrodynamics to explain single photon interference pattern. Which is impossible.

...is quite correct, and if you had just said that and no more, I would have no objection. But you didn't. You said other things that are not correct because they misrepresent what classical EM says.

 

[kurt101]

The problem is that a single photon, when detected, appears as a particle with a relatively well defined position, and not as a wave widely expanded in space. And yet the associated wave is widely expanded in space. It looks like a contradiction or at least a puzzle.

Can the EM wave and the photon be considered as two distinct phenomenon where the wave guides the photon?

 

[Demystifier]

Can the EM wave and the photon be considered as two distinct phenomenon where the wave guides the photon?

Yes, that's called Bohmian interpretation.

 

[kurt101]

Yes, that's called Bohmian interpretation.

It is my understanding that Bohmian mechanics says that the photon is guided by the quantum potential. I like the general idea of Bohmian mechanics, but not this aspect of it because it avoids explaining where the quantum potential came from other than Quantum Mechanics. So when you say that the explanation of the photon guided by the EM wave is a Bohmian mechanic interpretation, what does this mean exactly? Are you saying that Bohmian mechanics left the quantum potential piece unfinished and that Bohmians think there is a deeper mathematical explanation for the quantum potential that they have not yet figured out?

 

[Demystifier]

It is my understanding that Bohmian mechanics says that the photon is guided by the quantum potential. I like the general idea of Bohmian mechanics, but not this aspect of it because it avoids explaining where the quantum potential came from other than Quantum Mechanics. So when you say that the explanation of the photon guided by the EM wave is a Bohmian mechanic interpretation, what does this mean exactly? Are you saying that Bohmian mechanics left the quantum potential piece unfinished and that Bohmians think there is a deeper mathematical explanation for the quantum potential that they have not yet figured out?

In the context of Bohmian mechanics, the concept of quantum potential is somewhat outdated. It is much more correct to say that the particle (photon or whatever) is guided by the wave function. It is the same wave function that appears in standard quantum mechanics (QM). Bohmian mechanics does not say where does this wave function come from, but standard QM also does not say that, so in this sense Bohmian mechanics is not more mysterious than standard QM. For more about Bohmian mechanics see e.g. my "Bohmian mechanics for instrumentalists" linked in my signature below.

 

[EPR]

The EM field is a classical concept of the aggregate of many photons in motion with real values across space and should not be confused with matter waves(a purely quantum phenomenon guidied by the SE). It's hard to visualize but still...

 

[kurt101]

In the context of Bohmian mechanics, the concept of quantum potential is somewhat outdated. It is much more correct to say that the particle (photon or whatever) is guided by the wave function. It is the same wave function that appears in standard quantum mechanics (QM). Bohmian mechanics does not say where does this wave function come from, but standard QM also does not say that, so in this sense Bohmian mechanics is not more mysterious than standard QM. For more about Bohmian mechanics see e.g. my "Bohmian mechanics for instrumentalists" linked in my signature below.

If the Bohmian interpretation is simply that at some level a particle of sorts is guided by a wave of sorts then the Bohmian interpretation is an interpretation I subscribe to. It seems to be the simplest explanation for what we observe in experiments like the double slit and many others. More importantly it has the aspect of an interpretation that can be mathematically described and understood at a fundamental level even if we don't yet know what the underlying details are. I can't say the same for QFT.

I will try reading your paper, but I suspect it won't provide any additional explanation over Quantum Mechanics as to what is actually happening.

 

[PeterDonis]

A subthread on the Bohmian interpretation and special relativity has been moved to a new thread:

https://www.physicsforums.com/threads/bohmian-mechanics-and-special-relativity.981165/

Please keep this thread focused on the specific question raised in the OP.

 

[ilper]

What part of double slit mystery remains considering single slit can produce interference pattern as well? Does holography not fully explain those patterns behind any number of slits as a sort of "encoded image" of the slit(s)?

Does the word "focus" have any meaning in these kinds of experiments?

Holography deals with huge intensity of light and hence it is explained classicaly as a wave (EM wave). The paradox appears when you have separate particles (photons or other) coming one at a time (this Experiment is done). There is already no wave (physical) - just that particles somehow guided by the nonexising wave. In order to explain this Born introduced the probability wave. So that beast (particle - which is claimed to be point like) somehow sneaks tru both doors at the same time. In fact Feynman showed that it follows all possible paths from A to B at the same time. Nevertheless it is particle all the time whenever you try to observe it (it is born from an atom almost point, it is registered in atoms, on the way it is in a point (scattering on electrons - Compton).
All this is implemented in a single slit also. But with two slits if one observes one of the slits the wave vanishes (collapses) immediately and no interference pattern is observed (even if the particle didn't go tru it) . This can not be shown with one slit.
The focus does mean anything in this phenomena.