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0 pointscabinpark11y ago0 comments

I agree and disagree with what you're saying. I agree it is laziness and bad science that physicists stopped caring about the philosophical underpinnings of quantum mechanics but I disagree that it was because quantum mechanics not being the ultimate theory.

The reason most physicists don't think about the philosophical underpinnings has more to do with the way quantum mechanics is taught. Many of the founders were interested in the philosophical questions but after WWII you can see a sharp decrease in that aspect and more of the hardcore calculation and the philosophy kind of disappeared. Here [1] is a great talk that discusses this very point. Unfortunate for quantum mechanics because understanding the philosophical underpinnings is critical to understanding what quantum mechanics says and doesn't say. But, thanks to things like quantum computing and better experiments, interpretations is becoming more mainstream since there are experiments being planned (at least when I was heavily involved in the area in 2010) that would be able to test some of the claims made by different interpretations.

>We are all waiting for a better theory of physics. Of course rewriting the quantum theory in different forms, like this attempt, might help in getting there.

To me this is a contradiction. If we are all waiting for a better theory, then why are we re-writing the theory? A critical part of all the interpretations I've encountered [2] is making different ontological claims about quantum mechanics. Take Bohmian, which posits a guiding wave. Sure we can make some of the mathematics nicer, but we can't go very far without explaining what this 'guiding wave' is, which itself is rather ad hoc. Plus, how do we rectify it with Bell's theorem on hidden variables? To me, we can't really begin re-writing quantum mechanics without inevitably running into ontological statements.

But I still agree with your premise. I believe that by pushing the limits of quantum mechanics both scientifically and philosophically we will get a better grasp of what things to look for / where to look, for a deeper theory. Case in point, wavefunction collapse. Some might consider it a huge problem of quantum mechanics, but if you take a different ontological view, wavefunction collapse isn't that interesting or important. So maybe wavefunction collapse isn't as important and trying to develop a theory that doesn't have it is the wrong idea.

[1] http://pirsa.org/08090000/ [2] http://pirsa.org/C10002

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abdullahkhalids11y ago

I agree that progress in experimental abilities and QC is really forcing physicists to think carefully about what QM means. In fact the month of May saw three papers by major physicists about these deeper issues in QM [1,2,3] In my own humble capacity as a graduate student in physics, my research is about clearly understanding the divide between classical and quantum physics.

On the rewriting of theory, I should have been clearer. I meant that when you rewrite the theory you should think about ontology. Differences in ontology between different rewrites, as well as interpretations of those rewrites, will point to how quantum theory can be generalized.

I agree completely that quantum mechanics is taught horribly. Strangest of all are introductory quantum/modern physics courses that are meant to give students an intuition of quantum theory use the Copanhagen interpretation -the one that says the least about ontology and emphasizes calculations and empiricism.

I still stand behind my central claim. Let me be clearer. The mathematical model of classical physics says something about physical reality. The mathematical model of quantum mechanics says something very different about reality. Even if there are disagreements, we all agree that the ontology of classical physics is very much incorrect. Extrapolating from this I claim that the next theory of physics will have an ontology that will look nothing like that of quantum theory. As I have said previously, the ontology of quantum theory can be a means to an end (the next theory), but not the end itself.

[1] http://arxiv.org/abs/1405.1548 [2] http://arxiv.org/abs/1405.3483 [3] http://arxiv.org/abs/1405.7577

thedufer11y ago

My understanding is that the pilot wave theory is a non-local hidden variable theory, which doesn't contradict Bell's theorem at all. Of course, this presents ftl information transfer, presumed to be impossible, which is part of the reason such theories have been unpopular for so long.

danbruc11y ago

Non-locality does not imply the possibility of FTL information transfer - a theory can be non-local but make exploiting the non-locality impossible.

adamgravitis11y ago

This is a vitally important point. Many people still naively believe entanglement allows communication. Simultaneous randomness doesn't permit a signal.

GregBuchholz11y ago

>Plus, how do we rectify it with Bell's theorem on hidden variables?

I'm not a physicist, but I've always wondered about Caroline Thompson's work, like:

"Chaotic Ball" model, local realism and the Bell test loopholes

http://arxiv.org/abs/quant-ph/0210150

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