Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

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

quantamagazine.org

Post reply on HN
Print view View original

41–50 of 81 posts

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

#41

Post by millstone »

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 space.

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

#42

Post by pishpash »

frongpik wrote: post #35
pishpash wrote: post #21

Earlier quoted context omitted.

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.

The point is that waves are inherent in the description, whether it's complex numbers or amplitude + phase.

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

#43

Post by Enginerrrd »

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.

IMO, that assumption is the idea that decoherence occurs at all.

I really think Sean Carroll's ideas involving MWI and emergent spacetime from hilbert space provides a great deal of clarity.

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

#44

Post by vecter »

shadowgovt wrote: post #40
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…

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.

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

#45

Post by QuadmasterXLII »

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…

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

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

#46

Post by millstone »

jamiek88 wrote: post #36
deertick1 wrote: post #26

Earlier quoted context omitted.

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?

Not GP but since you asked, here it is: https://www.researchgate.net/publication/325462944_Planck%27...

The argument is: Planck's relation says that a photon's energy is in proportion to its frequency. But a higher-frequency photon oscillates more times per second. If you look at the energy of a single oscillation, you get a constant, regardless of frequency. This is remarkable and so we should reframe Planck's constant as the fundamental "energy per cycle."

The problem is that "energy of a single cycle" cannot be related to other measures of energy, e.g. the binding energy of an electron in the photoelectric effect. Basically it seems like unit sophistry.

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

#47

Post by karmakaze »

Here are the easy-viewing Wikipedia pages on Wheeler's delayed-choice experiment[0],

and my favorite the Delayed-choice quantum eraser[1].

[0] https://en.wikipedia.org/wiki/Wheeler%27s_delayed-choice_exp...

[1] https://en.wikipedia.org/wiki/Delayed-choice_quantum_eraser

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

#49

Post by analog31 »

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…

Indeed, early progress with QM in the first place required letting go of some expectations that were based on macroscopic phenomena. There was a certain effort to clarify those expectations so they could be gotten rid of. This is, at least, what I remember being taught about it.

So, maybe it's time for another round. ;-)

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

#50

Post by goatlover »

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.
Post reply on HN