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Closed loophole confirms the unreality of the quantum world (2018)

quantamagazine.org

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Re: Closed loophole confirms the unreality of the quantum world (2018)

#21

Post by pishpash »

choeger wrote: post #2

QM is obviously very true in the sense that it makes useful predictions (in that sense, truth is somewhat a quantity). But it is arguably very inelegant in its seemingly ad-hoc introduction of probability. Naturally, one would hope to one day get a more principled explanation of this randomness. What would be needed to make physicists search for such an explanation? Some kind of pattern in the "randomness"? Say, phot…

This is a misunderstanding of QM. Probability isn't what's unusual, it's the Born rule and the fact that the world doesn't use probability laws over real numbers but over complex numbers. That's what gives waves some sense of reality.

Re: Closed loophole confirms the unreality of the quantum world (2018)

#22

Post by tsimionescu »

AgentME wrote: post #4
choeger wrote: post #2

QM is obviously very true in the sense that it makes useful predictions (in that sense, truth is somewhat a quantity). But it is arguably very inelegant in its seemingly ad-hoc introduction of probability. Naturally, one would hope to one day get a more principled explanation of this randomness. What would be needed to make physicists search for such an explanation? Some kind of pattern in the "randomness"? Say, phot…

If you go with the Many-Worlds Interpretation, then trying to remove the randomness is nonsensical: the world just branches (in proportions as described by the Schrodinger equation), people on every branch have experience, and "randomness" is just what branch you find yourself on. The randomness of what branch you find yourself in is just like the randomness of what person you find yourself born as. All classical the…

On the contrary, it is still an open problem to rigorously derive the Born rule probabilities in MWI just from this perspective. Either way, the response will be equivalent to the Born rule: instead of positing that a measurement'outcome is proportional to the amplitude of the state, we posit that the number of branches in which an outcome happens is proportional to the amplitude of that outcome. Not sure why these are fundamentally different.

Also, the MWI idea of branching is no more satisfying or intuitive than the wave function collapse, which at least doesn't require an infinity of universes out of which some are much more probable than others.

Note also that there is only 1 of you in MWI, you just exist with different amplitudes in different states, but when interacting with another object, you become entangled with a single outcome and thus can no longer perceive the other states that other versions of you perceive. This is important, as otherwise physical quantities would not be properly conserved.

Re: Closed loophole confirms the unreality of the quantum world (2018)

#23

Post by mjfl »

withinboredom wrote: post #11

Has anyone ever considered that perhaps the particle/wave actually goes back in time?

Quantum mechanics definitively contains nonlocal effects (entanglement), which does seem to imply some kind of time traveling information, at least when combined with special relativity.

Re: Closed loophole confirms the unreality of the quantum world (2018)

#24

Post by shadowgovt »

vecter wrote: post #7
frongpik wrote: post #3

QM is the new Ptolematic system: it makes good predictions, but because it puts Earth in the center, the orbits become needlessly complex and artificial.

Explain how QM metaphorically “puts Earth in the center”.

That's the thing we don't know yet.

It's probably a good bet that we are going to discover that to rectify the complexities of QM, there is some assertion most people have fundamentally accepted and is quite uncomfortable to let go but is necessary to simplify the equations. I can't really guess what it's going to be though.

Re: Closed loophole confirms the unreality of the quantum world (2018)

#26

Post by deertick1 »

fungiblecog wrote: post #18

The problem is the insistence on the existence of particles at the quantum level. We know that quanta propagate like waves, but interact with classical level systems in discrete units. So we need to stop believing in discrete particles with distinct properties at the quantum level and come up with an explanation of why quantum waves appear particle-like at the classical level. Probably the answer will involve the way…

Lori Gardi, widely believed to be a crackpot, in my opinion has made a breakthrough in our interpretation od quantum mechanics.

If I understand her correctly, she proposes that the reason waves behave like particles is because they transfer energy essentially every zero-crossing : for example a photon is just one half of a wavelength of light.

She has a much more interesting explanation of what i am very poorly tryingto spit out here on youtube. Bear with, because honestly she is a whackadoo but she is a smart whackadoo.

Lemme know if you want a link to the video

Re: Closed loophole confirms the unreality of the quantum world (2018)

#27

Post by phkahler »

mjfl wrote: post #23
withinboredom wrote: post #11

Has anyone ever considered that perhaps the particle/wave actually goes back in time?

Quantum mechanics definitively contains nonlocal effects (entanglement), which does seem to imply some kind of time traveling information, at least when combined with special relativity.

I thought nonlocality was the obvious answer to "no hidden variables" but instead so many prefer to hidden multiverses instead. ;-)

Re: Closed loophole confirms the unreality of the quantum world (2018)

#28

Post by kanzenryu2 »

AgentME wrote: post #4
choeger wrote: post #2

QM is obviously very true in the sense that it makes useful predictions (in that sense, truth is somewhat a quantity). But it is arguably very inelegant in its seemingly ad-hoc introduction of probability. Naturally, one would hope to one day get a more principled explanation of this randomness. What would be needed to make physicists search for such an explanation? Some kind of pattern in the "randomness"? Say, phot…

If you go with the Many-Worlds Interpretation, then trying to remove the randomness is nonsensical: the world just branches (in proportions as described by the Schrodinger equation), people on every branch have experience, and "randomness" is just what branch you find yourself on. The randomness of what branch you find yourself in is just like the randomness of what person you find yourself born as. All classical the…

This is one thing I love about MWI... it has at least some kind of explanation for randomness. For every other interpretation they do some stuff and then choose a random outcome, and I want to ask "and how does that random step happen?"

Re: Closed loophole confirms the unreality of the quantum world (2018)

#29

Post by tsimionescu »

chii wrote: post #9
choeger wrote: post #2

QM is obviously very true in the sense that it makes useful predictions (in that sense, truth is somewhat a quantity). But it is arguably very inelegant in its seemingly ad-hoc introduction of probability. Naturally, one would hope to one day get a more principled explanation of this randomness. What would be needed to make physicists search for such an explanation? Some kind of pattern in the "randomness"? Say, phot…

> explanation of this randomness what if randomness is an inherent property of nature?

The problem is that QM doesn't allow randomness at the fundamental level. The Schrodinger equation is a linear differential equation, systems that evolve according to it evolve just like classical mechanics.

However, when you measure the state of such a system after however many steps of perfectly deterministic interactions you want, you find the system takes only one of the many possible states predicted by the Schrodinger equation, with a probability that depends on the amplitude of that state.

It is this discrepancy between the deterministic nature of the quantum world and the classical world, but the probabilistic nature of the crossing between them, that people find disconcerting.

MWI even does away with this to solve extent, explaining it as a kind of observation bias: as a particle interacts with a very independent system, it loses its ability to interact with itself (decoherence), and so we get many versions of the system each interacting with a single version of the particle, which stimulates classical physics for each version. From the perspective of any particular version of this system it is random with which particular version of the particle it interacts, even though at the universal level there is no randomness.

Re: Closed loophole confirms the unreality of the quantum world (2018)

#30

Post by vecter »

shadowgovt wrote: post #24
vecter wrote: post #7

Earlier quoted context omitted.

Explain how QM metaphorically “puts Earth in the center”.

That's the thing we don't know yet. It's probably a good bet that we are going to discover that to rectify the complexities of QM, there is some assertion most people have fundamentally accepted and is quite uncomfortable to let go but is necessary to simplify the equations. I can't really guess what it's going to be though.

That's not good enough. I want a specific claim about how one or more of the postulates of QM are likely to be incorrect (or even stranger, how they have to do with "putting Earth at the center", whatever that means, or some anthropomorphism baked into the postulate).

Saying "we don't know what we don't know" is both a tautology and completely useless. It's like my saying: "I believe that you committed a crime last week." You ask for more details about why I think that and what the crime was, and I reply "we just don't know." I hope you see how ludicrous that is.

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