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It’s time to admit quantum theory has reached a dead end

nautil.us

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Re: It’s time to admit quantum theory has reached a dead end

#221

Post by GoblinSlayer »

orbifold wrote: post #209
konschubert wrote: post #194

Earlier quoted context omitted.

Okay, cool, I’m 100% with you. But could we then please stop teaching the collapse nonsense to first year students? The logical inconsistencies of the collapse interpretation are an insult to their intellect.

The collapse just stands for the unknowable details of the interaction with the environment during measurement, a good quantum physics course will explain that and include experiments that make that clear. For instance the Stern-Gerlach experiment illustrates this well.

Decoherence is a consequence of interaction between particles in the coherent state, environment plays no role there, you can do all experiments in the vacuum and they will still work the same way, obviously.

Re: It’s time to admit quantum theory has reached a dead end

#222

Post by lenocinor »

I think the thing that honestly puzzles me is: before physicists learned physics, did their entire desire to be in the field spring from “shut up and calculate”? Or was there a time in their lives (especially when they were young) where they thought (or felt) a desire to get into physics to understand the underlying mechanisms that drive the universe? I feel like, at least for some people, the second thing must have been true. So, given that most quantum physicists seem uninterested in interpretations, where did this desire go? Did it disappear? Did the field get them to stop caring? Did it feel silly to them at some point? Did it feel hopeless? Or something else? I genuinely want to know.

Re: It’s time to admit quantum theory has reached a dead end

#223

Post by colordrops »

gus_massa wrote: post #216
adriand wrote: post #115

Earlier quoted context omitted.

I read somewhere that quantum mechanics is the most tested of all scientific theories. And it has been shown to be right, every time. Hawking espoused this idea he called “model dependent realism”. The idea is that every human understanding of reality is model-dependent, that is, it is not “reality” that we truly understand (we can’t) but rather in every case we have some model of reality that is useful in particular…

>> Can light and matter be both particle and wave? Or neither? We don’t know. But we know! The answer is neither. Light and matter are weird things that is impossible to describe with usual language, but they can be described very precisely with math language. The problem is that the equations are too complicated and difficult to use. They have been tested thoroughly, for example in particle accelerators but in exper…

This very precise description is still just a model and will in all likelihood be improved or even replaced one day as well.

Re: It’s time to admit quantum theory has reached a dead end

#224

Post by jayd16 »

chasil wrote: post #219
jayd16 wrote: post #159

Earlier quoted context omitted.

Is there something specific about oxidized metal that electrons need quantum tunneling to move through them? Why can't we just assume its normal conductivity?

Aluminum is extremely reactive, and the classic method of liberating this energy is through thermite reactions. Without the oxidation layer on aluminum, it would be an extremely hazardous substance. "Breaking bad" covered this with an etch-a-sketch. Sometimes chemistry can be surprising. https://en.wikipedia.org/wiki/Thermite

That's neat but I don't really follow. Why isn't the oxidation layer just a higher impedance material? Why is quantum tunneling required to explain a light switch?

Re: It’s time to admit quantum theory has reached a dead end

#225

Post by tus666 »

TheOtherHobbes wrote: post #43
tus666 wrote: post #3

Yes, but go back to philosophy not math. All the evidence suggests the "particle" interpretation of QM is simply wrong, that light or energy really is just a self propagating wave, which explains the double slit experiment cleanly, and is not incompatible with energy levels or quantization if formulated correctly. Experiments that claim to show light consists of particles need to be reassessed wearing a philosopher's…

No. "Particle" and "wave" are analogies. They're not even wrong, because they're not descriptions of what actually happens. The real problem is we don't have an analogy for what actually happens, because - by everyday expectations - the traditional interpretations are beyond weird. And the more recent interpretations are even weirder than that. It's likely - after Bell - that there's something non-local happening. An…

Wow I have heard some crackpot theories before, but then I came across "modern physics".

Re: It’s time to admit quantum theory has reached a dead end

#226

Post by tus666 »

mhh__ wrote: post #39
tus666 wrote: post #29

Earlier quoted context omitted.

We need to go back to the 1920s and start again. As the article explains, modern QM has hit a dead end, and it's little more than mathematical games that have not helped us understand reality.

Those mathematical games quite literally have helped us understand reality. The standard model made predictions, which were then tested.

Has it though? Do certain predictions presuppose a particular intepretation of reality? Does QM actually predict the double slit experiment?

Re: It’s time to admit quantum theory has reached a dead end

#227

Post by tus666 »

TheOtherHobbes wrote: post #61
renox wrote: post #24

Earlier quoted context omitted.

Yes, I never understood why light was considered 'particles' :-( As far as I understand it is because light can only be emitted by atoms with discrete energy levels, but (IMHO again) light is emitted by atoms with discrete energy levels because it is emitted when electrons jumps from one energy level to another and that the possible trajectory of electrons around the atoms aren't continuous, I don't see how this is r…

Light is considered a particle - or more accurately has particle-like behaviours in certain contexts - because you can count individual photons. The energy varies with frequency, and it arrives in discrete lumps at discrete locations. You can't have half a photon. It's all of a photon or no photon. It's one of Einstein's key insights, one of the foundations of quantum theory. In Quantum Field Theory you have quantum…

> Light is considered a particle - or more accurately has particle-like behaviours in certain contexts - because you can count individual photon

So how do they produce an inference pattern in the double slit experiment? I know you don't have an answer to that, but that's rather the point - neither does QM. Probability density does not explain an interference pattern. Only one thing does - that light is in fact a wave.

Re: It’s time to admit quantum theory has reached a dead end

#228

Post by dang »

sam_goody wrote: post #215
dang wrote: post #165

Earlier quoted context omitted.

Please correct wrong information without shaming others. We're trying to avoid the online callout/shaming culture here. https://hn.algolia.com/?sort=byDate&type=comment&dateRange=a... https://news.ycombinator.com/newsguidelines.html

dang, you read every comment on every thread? And you stay polite and interactive?! Are you sure you are human?

Nope–not even close. You're just seeing random data points and then the brain fills in the in-between spaces ;)

I wish I could do more actually - especially right now because the war is putting a lot of pressure on the container here.

Re: It’s time to admit quantum theory has reached a dead end

#229

Post by samus »

ravi-delia wrote: post #153
nwallin wrote: post #142

Earlier quoted context omitted.

The leading candidate for dark matter is that it's a soup of particles that interact gravitationally, but not via the electromagnic or strong nuclear force. If we're very, very lucky, it might interact via the weak nuclear force, which means there exists a slim theoretically possibility that we might be able to observe it interacting via the weak nuclear force. That being said, even if it does interact via the weak n…

It seems like I'm more hopeful for a quantum explanation of relativity than you are, but it's still sort of disquieting to think that there could be any number of fields that we just couldn't ever properly interact with. Even with gravity rolled in, there could still be a field that just doesn't interact at all. Hell, there could be hundreds. Creepy.

More likely, the symmetries that hide these fields would break down at energies that are way too high to ever reproduce in an accellerator or another lab experiment.

Re: It’s time to admit quantum theory has reached a dead end

#230

Post by samus »

Qem wrote: post #88
ricksunny wrote: post #57

Earlier quoted context omitted.

Could the would-be modern-day Copernicii be being stymied by modern-day academic funding structures and grant review committees?

I also have this impression. I think the current system lacks intellectual diversity. Lots of people pursuing the same few popular lines of inquiry, because if they get away from the herd, they have a hard time joining a big research group, getting funds and getting more people to read and cite their papers.

That problem is kind of inherent in the domain. In the past, significant research could be done with the meager stipends from generous nobles. Cutting-edge physics labs and supercomputers for astrophysical simulations are significantly more expensive.
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