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There exists a classical model of the photon after all

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Re: There exists a classical model of the photon after all

#21

Post by nilkn »

sampo wrote: post #18
cevn wrote: post #2

"Updating this with modern knowledge of quantised magnetic flux, we show that if you model a flux tube as a phase vortex in an inviscid compressible fluid, then wavepackets sent down this vortex obey Maxwell’s equations to first order; that they can have linear or circular polarisation; and that the correlation measured between the polarisation of two cogenerated wavepackets is exactly the same as is predicted by qua…

> How long would I have to study physics to be able to understand everything in this sentence? Just start reading David J. Griffiths: Introduction to Electrodynamics . A very well written textbook. The problem might be, if you don't know vector calculus, you might not be able to read this book, so you need to learn some vector calculus, too. Then start reading Introduction to Quantum Mechanics by Griffiths, too. Best…

I haven't read it, and it may be too advanced for this purpose, but Landau's books are generally held in extremely high regard and volume six of his Course of Theoretical Physics is on fluid mechanics.

For what it's worth, volumes two and three cover electrodynamics and quantum mechanics, respectively.

Re: There exists a classical model of the photon after all

#22

Post by angdis »

cevn wrote: post #2

"Updating this with modern knowledge of quantised magnetic flux, we show that if you model a flux tube as a phase vortex in an inviscid compressible fluid, then wavepackets sent down this vortex obey Maxwell’s equations to first order; that they can have linear or circular polarisation; and that the correlation measured between the polarisation of two cogenerated wavepackets is exactly the same as is predicted by qua…

It depends on what you mean by "understand everything". That is a very terse, densely packed sentence of jargon intended for practitioners but a physicist who is a skilled communicator could describe the main results to a high school kid. To be able to fully understand the arguments leading to those results... it would take very serious study and decently sophisticated mathematical background before even starting.

Re: There exists a classical model of the photon after all

#23

Post by sampo »

fixermark wrote: post #16
btilly wrote: post #12

They claim to have found a classical system that reproduces quantum mechanical effects. But if they manage to extend it to many particles, interacting, they will find that they have just come up with another interpretation of QM which is experimentally indistinguishable from the rest. And it wouldn't even be the first one. (Bohm's hidden variable theory has precedence.) Furthermore the "incompressible fluid" they pos…

What's the current status of Bohm's hidden variable theory? Does it stand up in light of the Bell test (I was under the impression that the Bell results suggest an arbitrary number of hidden variables would be necessary)?

> What's the current status of Bohm's hidden variable theory? Does it stand up in light of the Bell test

In "normal" quantum mechanics we have the wave-particle dualism. A particle behaves also like a wave, whatever that means.

In Bohm's hidden variable theory, also known as "pilot wave theory" the wave and the particles are separate. The pilot wave is a wave of unknown making (the theory does not say what it would be made of), and this wave follows the normal quantum mechanical behaviour. Then particles "ride" on this wave. So all the quantum mechanical wave effects happen in the pilot wave, and then the classical particle-like particles just follow theirs paths, already laid out by the wave.

Although "spooky action at a distance" is also experimentally verified, explaining this by postulating a wave that fills the whole universe, and explicitly reacts spookily over distances, makes the whole "spooky action at a distance" uncomfortable explicit in this theory, so it doesn't appeal to most physicists.

"The de Broglie–Bohm theory makes the same (empirically correct) predictions for the Bell test experiments as ordinary quantum mechanics. It is able to do this because it is manifestly nonlocal."

http://en.wikipedia.org/wiki/De_Broglie%E2%80%93Bohm_theory#...

Re: There exists a classical model of the photon after all

#24

Post by AnimalMuppet »

UhUhUhUh wrote: post #19
maaku wrote: post #13

Earlier quoted context omitted.

Reasoning from intuition has a terrible track record, I'm afraid.

Really? Did Einstein have empirical proof of his ideas?

For special relativity, yes. (Maxwell's equations plus the negative result of the Michaelson-Morley experiment.)

Re: There exists a classical model of the photon after all

#25

Post by sampo »

nilkn wrote: post #21
sampo wrote: post #18

Earlier quoted context omitted.

> How long would I have to study physics to be able to understand everything in this sentence? Just start reading David J. Griffiths: Introduction to Electrodynamics . A very well written textbook. The problem might be, if you don't know vector calculus, you might not be able to read this book, so you need to learn some vector calculus, too. Then start reading Introduction to Quantum Mechanics by Griffiths, too. Best…

I haven't read it, and it may be too advanced for this purpose, but Landau's books are generally held in extremely high regard and volume six of his Course of Theoretical Physics is on fluid mechanics. For what it's worth, volumes two and three cover electrodynamics and quantum mechanics, respectively.

> Landau's books

Landau's presentation is extremely condensed. Griffiths is much more friendly towards the reader.

I would compare Landau to Knuth's The Art of Computer Programming. Some people do read them, but the rest of us just hold them in extremely high regard :-).

Re: There exists a classical model of the photon after all

#26

Post by one-more-minute »

AnimalMuppet wrote: post #24
UhUhUhUh wrote: post #19

Earlier quoted context omitted.

Really? Did Einstein have empirical proof of his ideas?

For special relativity, yes. (Maxwell's equations plus the negative result of the Michaelson-Morley experiment.)

Also, Einstein's theories were a little bit more rigourous than "Well, the Luminiferous Aether sounds like bullshit to me"

Re: There exists a classical model of the photon after all

#27

Post by sp332 »

phkahler wrote: post #8

I hope this is as awesome as it sounds. It sums up everything I've been thinking about quantum physics, from "someone should look closer at Couders work" to "spooky action at a distance is BS" to "Quantum computers will never work - see spooky action".

Spooky action has been empirically demonstrated. https://arstechnica.com/science/2012/04/decision-to-entangle...

Re: There exists a classical model of the photon after all

#28

Post by pbhjpbhj »

maaku wrote: post #7
dkarapetyan wrote: post #4

Earlier quoted context omitted.

A lifetime, or long enough that it would feel like a lifetime. The real question to ask is that how you really want to spend your life? The fact that you're asking makes me think you've already chosen another path.

It does not take a lifetime. It took me about 6 months to cover upper-division electricity and magnetism and quantum mechanics, which is probably all that you would need to get the most basic but complete understanding of this paper.

Climbing to 20,000 ft from the 16,000 ft makes you think that climbing mountains is easier than it's going to be for the person at sea-level that you're advising. If you've been at 16,000 ft for some time even just that acclimatisation is going to make a huge difference.

Re: There exists a classical model of the photon after all

#29

Post by jarvist »

nilkn wrote: post #21
sampo wrote: post #18

Earlier quoted context omitted.

> How long would I have to study physics to be able to understand everything in this sentence? Just start reading David J. Griffiths: Introduction to Electrodynamics . A very well written textbook. The problem might be, if you don't know vector calculus, you might not be able to read this book, so you need to learn some vector calculus, too. Then start reading Introduction to Quantum Mechanics by Griffiths, too. Best…

I haven't read it, and it may be too advanced for this purpose, but Landau's books are generally held in extremely high regard and volume six of his Course of Theoretical Physics is on fluid mechanics. For what it's worth, volumes two and three cover electrodynamics and quantum mechanics, respectively.

Landau/Lifshitz are freely available on the Internet archive:

https://archive.org/search.php?query=creator%3A%22L.D.+Landa...

Re: There exists a classical model of the photon after all

#30

Post by pbhjpbhj »

phkahler wrote: post #8

I hope this is as awesome as it sounds. It sums up everything I've been thinking about quantum physics, from "someone should look closer at Couders work" to "spooky action at a distance is BS" to "Quantum computers will never work - see spooky action".

It's quite exciting to see these sorts of papers.

What fascinates me is that we have achieved so much in the "quantum age" of the past century using the models derived from a quantum mechanical approach to physics. That the bedrock [or lack of one] of that could be removed and provide a better, more consistent, approach seems so counter-intuitive. But then one recalls how long the Newtonian or Aristotelian approaches [or any other such system] stood.

Also would this be a return to universal models with an aether: wonder how Michelson-Morley works with "flux tubes"?

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