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There exists a classical model of the photon after all

lightbluetouchpaper.org

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

#51

Post by clavalle »

itistoday2 wrote: post #35
clavalle wrote: post #15

Earlier quoted context omitted.

It can take a bit of unpacking, but someone with some sort of college level physics and mathematics background can use Wikipedia to get a basic understanding of what they are talking about. They are basically saying that the quantum mechanical 'strangeness' of light can be explained with classical, deterministic, physics. It is not necessary to have a separation in which quantum mechanics predominates at one level an…

Pilot wave theory has been known for decades. So can someone explain how whatever they're talking about is different/new?

So they claim that up until now pilot wave theory hasn't been able to explain entanglement while remaining consistent with Maxwell's equations.

They are not saying they came up with pilot wave theory, only that they've removed a sticking point.

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

#52

Post by saalweachter »

Dylan16807 wrote: post #41
btilly wrote: post #17

Earlier quoted context omitted.

I don't know and don't keep track. I lost interest after realizing that it can be made compatible with any possible observation. I'm personally a fan of the Everett interpretation. Also called the many worlds. Which is what you get if you assume that quantum mechanics applies to the observer. Then the act of observation throws the observer into a superposition of possible states where different things were observed.…

>good reason to believe that quantum mechanics does not describe humans One simple idea is that the more energy and matter you shove into the wave function, the easier it is to collapse, so that at the macro level quantum effects are rendered impossible.

Ah, but macro-level systems can amplify quantum effects. For instance, the human eye -- under the right conditions -- is sensitive to individual photons.

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

#53

Post by davorak »

IsTom wrote: post #43
btilly wrote: post #17

Earlier quoted context omitted.

I don't know and don't keep track. I lost interest after realizing that it can be made compatible with any possible observation. I'm personally a fan of the Everett interpretation. Also called the many worlds. Which is what you get if you assume that quantum mechanics applies to the observer. Then the act of observation throws the observer into a superposition of possible states where different things were observed.…

There's a problem with with many-worlds that I haven't seen convincingly refuted: when collapsing superposition of two states you might need to (or rather almost always) need the ratio of worlds with outcome A to worlds with outcome B to be irrational. So unless you create a continuum of new worlds each time it won't work.

> when collapsing superposition of two states you might need to (or rather almost always) need the ratio of worlds with outcome A to worlds with outcome B to be irrational. So unless you create a continuum of new worlds each time it won't work.

Has this been shown? I would want any such proof inspected for hidden continuum assumptions existing in the probability calculations, thus leading to irrational probabilities.

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

#54

Post by btilly »

Dylan16807 wrote: post #41
btilly wrote: post #17

Earlier quoted context omitted.

I don't know and don't keep track. I lost interest after realizing that it can be made compatible with any possible observation. I'm personally a fan of the Everett interpretation. Also called the many worlds. Which is what you get if you assume that quantum mechanics applies to the observer. Then the act of observation throws the observer into a superposition of possible states where different things were observed.…

>good reason to believe that quantum mechanics does not describe humans One simple idea is that the more energy and matter you shove into the wave function, the easier it is to collapse, so that at the macro level quantum effects are rendered impossible.

The problem is that there is absolutely no experimental or theoretical reason to believe that quantum states ever collapse. And there is an explanation for why we would perceive collapse even if there is none.

If you take those ideas seriously, you're forced into the Everett interpretation.

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

#55

Post by Symmetry »

IsTom wrote: post #43
btilly wrote: post #17

Earlier quoted context omitted.

I don't know and don't keep track. I lost interest after realizing that it can be made compatible with any possible observation. I'm personally a fan of the Everett interpretation. Also called the many worlds. Which is what you get if you assume that quantum mechanics applies to the observer. Then the act of observation throws the observer into a superposition of possible states where different things were observed.…

There's a problem with with many-worlds that I haven't seen convincingly refuted: when collapsing superposition of two states you might need to (or rather almost always) need the ratio of worlds with outcome A to worlds with outcome B to be irrational. So unless you create a continuum of new worlds each time it won't work.

The Everett Interpretation is best thought of as the idea that collapse just doesn't happen. Which means that there aren't discrete integer worlds but only higher and lower amplitudes. If you had discrete worlds that would also be a problem because you could change how many worlds you had by how you did the math.

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

#56

Post by btilly »

IsTom wrote: post #43
btilly wrote: post #17

Earlier quoted context omitted.

I don't know and don't keep track. I lost interest after realizing that it can be made compatible with any possible observation. I'm personally a fan of the Everett interpretation. Also called the many worlds. Which is what you get if you assume that quantum mechanics applies to the observer. Then the act of observation throws the observer into a superposition of possible states where different things were observed.…

There's a problem with with many-worlds that I haven't seen convincingly refuted: when collapsing superposition of two states you might need to (or rather almost always) need the ratio of worlds with outcome A to worlds with outcome B to be irrational. So unless you create a continuum of new worlds each time it won't work.

Why is this a problem? This complaint looks to me much like someone complaining about the Pythagorean theorem because it results in irrational numbers. (And yes, historically there were such complaints. And no, that is not a good reason to discard that theorem.)

A system described by physics evolves according to the laws of physics. We find the result surprising. But that is because we have bad intuition, not because physics is fundamentally broken.

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

#57

Post by darkmighty »

mikeash wrote: post #39
UhUhUhUh wrote: post #19

Earlier quoted context omitted.

Really? Did Einstein have empirical proof of his ideas?

Einstein won his Nobel Prize for explaining the photoelectric effect, a measured phenomenon that didn't have an adequate explanation. His work on brownian motion showed that the observations of the movements of small particles can be explained by the nature of fluids as being made up of small particles (i.e. molecules). Special relativity is what you get when you combine the seemingly contradictory observed phenomena…

Einstein's idea of "intuition" is bastardized sometimes. He didn't mean "Having a common-sense opinion that something is wrong or right" as intuition, he just meant "Think really hard about the underlying principles and reach a conclusion", as opposed to "Make an arbitrary mathematical model, try to fit the data, iterate".

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

#58

Post by tjradcliffe »

This paper has a variety of issues, the most glaring of which is that their "explanation" of the experimental violation of Bell's inequalities (specifically the CHSH form that has been realized in many experiments on polarization) is dependent on a static setup of precisely the kind that Aspect's experiments were intended to avoid.

Aspect's work is one of the most beautiful pieces of careful and precise experimental testing of an idea in the past half-century, and while it has been attacked from many perspectives it is still a very robust argument for the non-locality of reality. One of the important things about it is that the polarization direction was switched in a quasi-random way after the photons had left the source. Variations on this trick have been performed since, and they all agree with the predictions of quantum theory.

The authors say in this paper "The CHSH assumption is not true in Faraday's model. Instead there is prior communication of orientation along phase vortices such as(4), communication which the CHSH calculation excludes by its explicit assumption."

In experiments like Aspects, prior communication is ruled out because the experimental setup is varied in one arm of the apparatus outside forward light cone of the other photon. Each photon gets detected before the other one could possibly know (based on signalling at the speed of light) what polarizer orientation it should be lined up with.

So this is an interesting bit of work that might be useful in creating photonic quasi-particles in magnetic fluids that would allow for study of photon properties that might be difficult to get an experimental handle on otherwise, but the claim that they have a classical model that violates Bell's inequalities in a way that is relevant to the actual experimental work done in this area is considerably overblown.

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

#60

Post by tjradcliffe »

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…

The only caveat to this is the ontological status of Faraday's "lines of force". Their model is based on these, and so far as anyone knows they are just a conceptual or pedagogical convenience. They have a quantitative meaning (you can actually calculate the "density of lines of force" between two charges or magnetic dipoles) but they aren't really good for much. They are generally mentioned in passing in intro or intermediate E&M courses, but mostly as a matter of historical interest.

If they could be shown to have independent effect of the kind that the vector potential was shown to have via the Ahronov-Bohm effect, then this whole approach to quantization would become extremely interesting. Otherwise, you're right: it's just another interpretation of QM, and not a very interesting one at that (despite their claims, as I explained in a separate comment, they can't reproduce the experimental violations of the CHSH inequalities in Aspect's and other experiments that introduce time-variation to precisely rule out the kind of prior communication they are arguing for.)

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