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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)

#31

Post by l33tman »

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…

But it isn't that simple. There isn't a "proportional split" that can depend on the Schrödinger Equation. This is exactly why QM behaves non-intuitively in the first place - you can't add up probabilities from individual events, you have to add complex numbers and only at the "end" you square them and get probabilities. So it's would be a nice analogue in MWI that the world just splits up and that's why probabilities arise, but it doesn't fit.. :/

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

#32

Post by sls »

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.

Have you ever actually looked at the Schrödinger equation? [1] It's pretty simple. If you've had freshman physics, you can learn enough to derive it in a matter of days or at most weeks. There's not a lot of room in there for the kind of thing you are suggesting.

It's much more plausible that the uncomfortable human-centric thing we need to let go is the idea that our perceptions about macroscopic reality should be indicative of how things actually are.

[1] https://en.wikipedia.org/wiki/Schrodinger_equation

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

#33

Post by WantonQuantum »

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…

This answer to this is actually known and is a consequence of Heisenberg's uncertainty principle. Here's a youtube video about it: https://www.youtube.com/watch?v=QPAxzr6ihu8

Of course, Heisenberg's uncertainty principle is a mathematical description of observed behaviour so one could rightly argue that it doesn't really explain anything - it merely describes things.

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

#34

Post by miltondts »

sls wrote: post #32
shadowgovt wrote: post #24

Earlier quoted context omitted.

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.

Have you ever actually looked at the Schrödinger equation? [1] It's pretty simple. If you've had freshman physics, you can learn enough to derive it in a matter of days or at most weeks. There's not a lot of room in there for the kind of thing you are suggesting. It's much more plausible that the uncomfortable human-centric thing we need to let go is the idea that our perceptions about macroscopic reality should be i…

Circles are also simpler than ellipses. Maybe that's a clue. Maybe we need a more complicated equation that makes the phenomena more understandable.

EDIT: To stretch the metaphor a bit more. Maybe QFT is the analogous of the solar system described with epicycles.

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

#35

Post by frongpik »

pishpash wrote: post #21
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.

The probability waves may be regular real waves, it's just convenient to describe amplitude and phase at every point with a complex number. We could describe water surface the same way, but it wouldn't mean water is complex.

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

#36

Post by jamiek88 »

deertick1 wrote: post #26
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 tryin…

Why is it always YouTube videos with these (let’s generously say)esoteric ideas and never a link to a paper or essay?

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

#37

Post by shadowgovt »

sls wrote: post #32
shadowgovt wrote: post #24

Earlier quoted context omitted.

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.

Have you ever actually looked at the Schrödinger equation? [1] It's pretty simple. If you've had freshman physics, you can learn enough to derive it in a matter of days or at most weeks. There's not a lot of room in there for the kind of thing you are suggesting. It's much more plausible that the uncomfortable human-centric thing we need to let go is the idea that our perceptions about macroscopic reality should be i…

That would, indeed, be an uncomfortable thing to let go of, since they are our direct perceptions.

Relativity tells us things get weird at high velocities, but our daily perception is basically correct. Quantum theory seems to suggest that solid, tangible reality isn't at all like our day-to-day experience. That's a pretty decent leap to ask of people.

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

#38

Post by frongpik »

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.

Plato and a few others told about the world of ideas and the world of matter: both exist and are connected somehow. I wonder if QM is this bridge between the two worlds and the wrong assumption we make is that QM describes the world of matter. In other words, the probability waves may actually exist, but they exist in the world of math, and the real question is how exactly the two worlds are connected.

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

#39

Post by nabla9 »

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.

Kind of. Quantum states don't have on place or time. Only objects that share those states have locations.

The concepts like locality and physical object have become more specific over time.

Before QM, principle of locality in physics matched the common sense of locality in every sense. Object is directly influenced only by its immediate surroundings. Objects have locations. Field must mediate the action over distance.

After QM was developed, principle of locality in physics became more refined. Quantum states don't have location in space and time. They are not 'physical objects' themselves. Quantum states is everywhere in time and space where objects sharing that state are, and everything correlates perfectly over time and space.

Before QM, something like quantum-state would have been called a non-local thing. In current more refined meaning it's not breaking locality. Non-local instant quantum state 'hovering over wast distances of space and time' is OK as long as causality is local and moves at the speed of light.

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

#40

Post by shadowgovt »

vecter wrote: post #30
shadowgovt wrote: post #24

Earlier quoted context omitted.

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 w…

It's been awhile since I thought deeply about epicycles, but if my memory can be trusted... They weren't incorrect. They did a decent job of predicting the motions of the planets given the assumption that Earth was pegged at the center of the coordinate frame (which then required a whole bunch of "hidden behavior" in terms of non-apparent phenomena dictating the rotation of all other bodies).

Re-framing the whole system to be heliocentric allowed for the massive simplification of Kepler's Laws (and, not too much later, the further simplification of describing Kepler's laws via Newton's law of gravitational attraction).

We currently have an understanding of QM that doesn't reconcile well with macroscopic observation and requires a lot of intuitions to be broken (including, possibly, the singular nature of existence, time-forward causality, or lightspeed-constrained information locality). I can't help but wonder if there's some equivalent to "Assuming Earth is the center of the coordinate frame" that we currently do that forces these unintuitive (though working) solutions.

The solar system moved in epicycles because "it just did," until several leaps of intuition allowed us to see how it didn't. I wonder if there are similar leaps of intuition waiting on the horizon to allow us to explain quantum entanglement without nonlocal information sharing (hidden variables, we have shown, is not it).

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