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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)

#51

Post by shadowgovt »

vecter wrote: post #44
shadowgovt wrote: post #40

Earlier quoted context omitted.

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 sys…

> We currently have an understanding of QM that doesn't reconcile well with macroscopic observation and requires a lot of intuitions to be broken Why should physics care about human "intuition" at the macroscopic level? That's an incredibly anthropic point of view to take on a cosmos that couldn't care less if we didn't exist.

When Newton developed the theory of gravity it wasn't intuitive that all matter in the universe attracts all other matter. But also wasn't incompatible with our intuitions---it was learnable.

What I see in QM right now "smells" like we're having to compromise too many intuitions to reconcile what the experiments are showing us with the way we expect the universe ought to be working. I agree that the universe is under no obligation to work the way we expect it to---problem, what we have right now in QM is a lack of agreement on how to even rework our intuitions to match our observations and the reality the theory describes. That suggests to me that---much like epicycles, or like gravity being separated from acceleration before relativity---the stories we are telling ourselves about what we see are still too complicated, and a simpler explanation that requires us to sacrifice fewer pieces of intuition has not yet been reached.

This is, to be clear, extrapolation. I have no way to know whether such simplification exists or whether we have hit the boundary where nature actually refuses to conform in such a way to our senses and minds that we can change our intuitions to follow her. It's not impossible that this is the case. But if it is, it's a break from the pattern of physics discovery up to this point in human history.

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

#52

Post by shadowgovt »

QuadmasterXLII wrote: post #45
vecter wrote: post #30

Earlier quoted context omitted.

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…

The “putting the earth in the center” is wave function collapse. If you get rid of wave function collapse then all the paradoxes go away except that our experience is a tiny branch of a massive tree

That might be the case. But something still smells in the many worlds theory---it's hard to reconcile conservation of energy or mass with the notion of an infinitely branching multiverse, and if there is no way to interact with those other branches, are they real or just a story we're telling ourselves to try and justify the math?

if they are just a story, it feels like a complicated story to get to the goal.

At the same time, I completely agree that the story of wave function collapse also smells. It creates a distinction between observer and observed reality, and that creates its own set of paradoxes (we can put Schrodinger's cats in nested boxes all day long, and some of the boxes even include experimenters who think they are observing the cat, but experimenters outside the lab don't agree with them that they are the observers!).

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

#53

Post by nine_k »

goatlover wrote: post #50
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…

Replace particles with fields in which particles are the result of excitation in the fields. Fields are the fundamental stuff of reality, and particles are emergent from field interactions.

Fields are continuous. E.g. electromagnetic field in the classic electrodynamics is continuous. But its waves, photons, show quantum, discrete properties — see the photo effect. It would be easy if there were some common grid, but it's not the case. You can make photons with whatever energy from a continuous spectrum, but photons of each frequency will carry its own quantum (Latin for "amount") of energy, in discrete portions.

Why is this happening? That's the question worth 1000 Nobel prizes.

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

#54

Post by nine_k »

millstone wrote: post #41
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…

We should distinguish between quantization, and "discrete particles with distinct properties." For example, the photoelectric effect demonstrates that light is quantized, but individual photons have no distinct identity whatsoever. "Number of particles" is an observable like position, momentum, spin, etc. It is a quantum property which may or may not commute with other properties, and occupies the same conceptual spa…

Number of quanta is observable. You can count photons.

OTOH it does not imply that a photon is a "particle" in the same sense a breadcrumb is, with a well-defined diameter, shape, or borders. It is a portion of energy of electromagnetic field that was sufficient to yank an election from a photo element's crystallic grid.

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

#55

Post by maria_weber23 »

WantonQuantum wrote: post #33
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.

Heisenberg's uncertainty principle should probably be put the rest at this point. From the beginning it was more "capturing" our inability to move beyond the physics as we know it. It's like tying your shoe laces. I always found it fascinating how firmly most physicists believe in the equations someone came up with, just because it agree with measurements. I mean that's real nice and all, but just because something agrees with measurements, doesn't make it a fact. There are literally infinite ways to create equations that satisfy measurements. But sure, a few decades of research in the early 20th century and that's it. This is all we can do. Let's just accept that lol.

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

#56

Post by nine_k »

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…

The system of epicycles was made of pretty simple, easy things: circles. It's when they were combined things went complicated.

Same with Schrödinger equation: it's very simple for one particle in an empty Universe, but things go more complicated when more particles are considered.

There is no guarantee that a different approach can replace QM and describe things in a simpler way. But I suspect that attempts to look for such approaches are not useless.

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

#58

Post by benlivengood »

shadowgovt wrote: post #52
QuadmasterXLII wrote: post #45

Earlier quoted context omitted.

The “putting the earth in the center” is wave function collapse. If you get rid of wave function collapse then all the paradoxes go away except that our experience is a tiny branch of a massive tree

That might be the case. But something still smells in the many worlds theory---it's hard to reconcile conservation of energy or mass with the notion of an infinitely branching multiverse, and if there is no way to interact with those other branches, are they real or just a story we're telling ourselves to try and justify the math? if they are just a story, it feels like a complicated story to get to the goal. At the…

> That might be the case. But something still smells in the many worlds theory---it's hard to reconcile conservation of energy or mass with the notion of an infinitely branching multiverse, and if there is no way to interact with those other branches, are they real or just a story we're telling ourselves to try and justify the math?

Looking at the multiverse as branching is where the confusion comes in. There's one Universal wave-function. Why we don't experience the wave-function directly is the mystery.

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

#59

Post by GoblinSlayer »

shadowgovt wrote: post #52
QuadmasterXLII wrote: post #45

Earlier quoted context omitted.

The “putting the earth in the center” is wave function collapse. If you get rid of wave function collapse then all the paradoxes go away except that our experience is a tiny branch of a massive tree

That might be the case. But something still smells in the many worlds theory---it's hard to reconcile conservation of energy or mass with the notion of an infinitely branching multiverse, and if there is no way to interact with those other branches, are they real or just a story we're telling ourselves to try and justify the math? if they are just a story, it feels like a complicated story to get to the goal. At the…

In MWI energy and mass conserve, it's the state that branches.

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

#60

Post by GoblinSlayer »

shadowgovt wrote: post #51
vecter wrote: post #44

Earlier quoted context omitted.

> We currently have an understanding of QM that doesn't reconcile well with macroscopic observation and requires a lot of intuitions to be broken Why should physics care about human "intuition" at the macroscopic level? That's an incredibly anthropic point of view to take on a cosmos that couldn't care less if we didn't exist.

When Newton developed the theory of gravity it wasn't intuitive that all matter in the universe attracts all other matter. But also wasn't incompatible with our intuitions---it was learnable. What I see in QM right now "smells" like we're having to compromise too many intuitions to reconcile what the experiments are showing us with the way we expect the universe ought to be working. I agree that the universe is under…

Round Earth and heliocentrism were counterintuitive too and people struggled a lot to understand them, it's not unprecedented. Ironically Aristotle refuted heliocentrism with the same argument, that heliocentrism doesn't correspond to observation.

We have intuition to understand QM, people struggle with myths, not lack of intuition. Absence of conservation of energy is one of those myths, only those myths need to be sacrificed.

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