Jump to content


Photo
- - - - -

Quantum mechanics (split from nature of light)


  • Please log in to reply
10 replies to this topic

#1 MigL

MigL

    Primate

  • Senior Members
  • 2,865 posts
  • LocationSt. Catharines, Ontario, Canada

Posted 19 May 2017 - 06:05 PM

As I've communicated in PMs with the OP, and further to Studiot's excellent historical summary, I would suggest that the wave model is neatly represented by Maxwell's equations, while the modern quantum particle model has nothing at all to do with classical corpuscles/particles, but rather photons are excitations of the quantized EM field ( in accordance with quantum field theory ). And while both are excellent models which help us make many valid predictions when applied appropriately, they both still have problems providing satisfactory answers in certain situations like the double slit.


  • 0

#2 Strange

Strange

    SuperNerd

  • Senior Members
  • 12,885 posts
  • Location珈琲店

Posted 19 May 2017 - 06:12 PM

Surely, the results of the double slit experiment are exactly as predicted by quantum theory?


  • 0

#3 MigL

MigL

    Primate

  • Senior Members
  • 2,865 posts
  • LocationSt. Catharines, Ontario, Canada

Posted 19 May 2017 - 06:59 PM

They are but...

I can have 100 double slit experiments set up all across the US.

Pass exactly one photon through the experiment onto a transparent photographic plate so that I get a single spot.

Upon collecting all the plates together the following day, and superimposing them, I get a diffraction pattern.

There is no possibility of entanglement of any sort in this situation, so how do the photons 'know' where to land ?

 

That is what I mean by lack of 'satisfactory' answers.

Even modified wave/particle models ( remember the deBroglie pilot wave ? ) wouldn't account for such behavior.


Edited by MigL, 19 May 2017 - 07:06 PM.

  • 1

#4 Strange

Strange

    SuperNerd

  • Senior Members
  • 12,885 posts
  • Location珈琲店

Posted 19 May 2017 - 07:24 PM

There is no possibility of entanglement of any sort in this situation, so how do the photons 'know' where to land ?

 

 

Entanglement has nothing to do with it. And they don't know where to land. There is just a higher probability of landing in certain locations. This is explained by the non-local behaviour of photons - you can describe this as the photon going through both slits, or by a pilot wave, or any other interpretation.  I don't see a problem.


  • 0

#5 MigL

MigL

    Primate

  • Senior Members
  • 2,865 posts
  • LocationSt. Catharines, Ontario, Canada

Posted 19 May 2017 - 08:40 PM

I agree with all you say Strange and don't see a problem either, but somehow the end results aren't 'satisfying'.

I guess it as more to do with the 'why' rather than the 'how', because neither a wave or a particle would act in such a manner.

Only a probability distribution/wave would ( not duality but trinity ? )

And I realize no-one gives a damn about my 'satisfaction', but even R Feynman felt that way.


Edited by MigL, 19 May 2017 - 08:47 PM.

  • 1

#6 swansont

swansont

    Evil Liar (or so I'm told)

  • Moderators
  • 36,454 posts
  • LocationWashington DC region

Posted 19 May 2017 - 08:57 PM

They are but...

I can have 100 double slit experiments set up all across the US.

Pass exactly one photon through the experiment onto a transparent photographic plate so that I get a single spot.

Upon collecting all the plates together the following day, and superimposing them, I get a diffraction pattern.

There is no possibility of entanglement of any sort in this situation, so how do the photons 'know' where to land ?

 

That is what I mean by lack of 'satisfactory' answers.

Even modified wave/particle models ( remember the deBroglie pilot wave ? ) wouldn't account for such behavior.

 

 

You get 1000 people across the country to flip a coin, or roll a die. They all send their data in. How do the coins or dice "know" how to land? (And these are purely classical systems!)


  • 2

Minutus cantorum, minutus balorum, minutus carborata descendum pantorum          To go to the fortress of ultimate darkness, click the up arrow ^

I am not a minimum-wage government shill.             Forget it, Jake — it's Crackpottown.

My SFN blog: Swans on Tea                                                           

 

 

                                                                                                                     

 

 


#7 MigL

MigL

    Primate

  • Senior Members
  • 2,865 posts
  • LocationSt. Catharines, Ontario, Canada

Posted 20 May 2017 - 01:42 AM

Never thought of it that way.

Still leaves wanting 'more' of an answer though.


  • 0

#8 Mordred

Mordred

    Resident Expert

  • Resident Experts
  • 4,463 posts

Posted 20 May 2017 - 02:06 AM

As I've communicated in PMs with the OP, and further to Studiot's excellent historical summary, I would suggest that the wave model is neatly represented by Maxwell's equations, while the modern quantum particle model has nothing at all to do with classical corpuscles/particles, but rather photons are excitations of the quantized EM field ( in accordance with quantum field theory ). And while both are excellent models which help us make many valid predictions when applied appropriately, they both still have problems providing satisfactory answers in certain situations like the double slit.

The QFT treatment of observable action, opened my eyes to a question I am still working on developing an answer for.

To be 100% clear I am not stating the following is occurring though I do have to consider the possibility. Especially considering that this isn't uniquely my idea and has been considered.

I mentioned before numerous times that it takes a quanta of energy to cause observable action. In point of detail the Planck constant is often called a quanta of action. (little side note).

Now under QFT all particles are field excitations. In essence field vibrations/waves. Good so far everything I mentioned above is standard concordance under QFT treatment.

Now consider that waves generate constructive and destructive interference.

This is extremely well known. Waves of identical frequencies will combine to form a resultant waveform whose value is a sum of the two previous waveforms.

This follows from the Principle of superposition. The common classical descriptive being.

"When two waves interfere, the resulting displacement of the medium at any location is the algebraic sum of the displacements of the individual waves at that same location"

Now there is a double slit experiment in Classical called the Young's Double slit experiment. This is a precurser to QM done back in 1801.

https://en.m.wikiped...slit_experiment

Wiki mentions this.

Now consider further that the particle like characteristics is defined and cobstrained by a quanta of action confined by the Compton wavelength.

So here is my query, Is Young in essence correct even under QFT treatment?

The second question is how many photons (quanta) are produced as a direct result of constructive interference after the two beams pass both slits?

Now consider the above but add spin statistics. See where I am going?

Instead of restricting ourselves to the Quantum mechanical spin statistics explanation or the Young's classical explanation perhaps we should ask if its a conbination of both.

However there is a few problems with this.

The experiment has been performed with 1 photon (quanta) at a time, under the wave it should have divided its energy between the two slits then recombine after. However this didn't occur.

Ain't science fun lol PS if you take a single quanta and split the energy between two slits how can you observe it unless the two waves recombine after?

Edited by Mordred, 20 May 2017 - 04:03 AM.

  • 0
http://www.einsteins.../LightCone.html
http://cosmology101.wikidot.com/main
http://cosmocalc.wikidot.com/start
If you wish to change the rules, you must first understand the rules.

#9 Sensei

Sensei

    Scientist

  • Senior Members
  • 3,239 posts

Posted 20 May 2017 - 04:02 AM

They are but...
I can have 100 double slit experiments set up all across the US.
Pass exactly one photon through the experiment onto a transparent photographic plate so that I get a single spot.
Upon collecting all the plates together the following day, and superimposing them, I get a diffraction pattern.
There is no possibility of entanglement of any sort in this situation, so how do the photons 'know' where to land ?

 
Excellent thought experiment. IMHO worth to try in the reality.
 
ps. Random number generators, are generating over and over the same numbers, when you use the same srand() initial value ;)
 

You get 1000 people across the country to flip a coin, or roll a die. They all send their data in. How do the coins or dice "know" how to land? (And these are purely classical systems!)


From these data you would not get any diffraction pattern...

Edited by Sensei, 20 May 2017 - 04:09 AM.

  • 0

#10 Mordred

Mordred

    Resident Expert

  • Resident Experts
  • 4,463 posts

Posted 20 May 2017 - 04:04 AM

I agree with that but in the two slit superposition isn't entanglement. Its constructive interferance which isn't quite the same as entanglement. Or rather as far as the superposition term is used for the two slit.

However the experiment has also been done with entangled particles. In the effort to gain a greater understanding.

I always liked this gif.

I92rE.gif


Edited by Mordred, 20 May 2017 - 05:21 AM.

  • 0
http://www.einsteins.../LightCone.html
http://cosmology101.wikidot.com/main
http://cosmocalc.wikidot.com/start
If you wish to change the rules, you must first understand the rules.

#11 swansont

swansont

    Evil Liar (or so I'm told)

  • Moderators
  • 36,454 posts
  • LocationWashington DC region

Posted 20 May 2017 - 01:51 PM

Never thought of it that way.

Still leaves wanting 'more' of an answer though.

 

 

It's probabilistic. What more do you need? Unless you are delving into metaphysics, that is.


  
From these data you would not get any diffraction pattern...

 

I did not claim you would; I pointed out that it was a classical example. But that's not the point. You would get a pattern, which would be the same probability distribution you would expect if it had been done by one person with a fair coin or die.


  • 0

Minutus cantorum, minutus balorum, minutus carborata descendum pantorum          To go to the fortress of ultimate darkness, click the up arrow ^

I am not a minimum-wage government shill.             Forget it, Jake — it's Crackpottown.

My SFN blog: Swans on Tea                                                           

 

 

                                                                                                                     

 

 





0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users