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Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

quantamagazine.org

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Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#51

Post by patcon »

kikokikokiko wrote: post #44

To me, the fact that quantum mechanics is intrinsically "random" and unknowable beforehand, is what makes living bearable in this universe as a sentient being. If we, two legged viruses that we are, could reach a level of understanding that could show the universe to be fully deterministic and every future state to be knowable given that you know the current states, then this human condition would be impossible to st…

agreed! and here you go! https://thoughtforms.life/symposium-on-the-platonic-space/

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#52

Post by danbruc »

Do I get this right? Wave function collapse due to measurements is not real, the wave function evolves unitarily all the time. But as quantum states get amplified into the macroscopic world, superposition states are somehow amplified asymmetrically which makes it look like wavefunction collapse.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#53

Post by spot5010 »

Nevermark wrote: post #35
spot5010 wrote: post #9

Earlier quoted context omitted.

The part that I have trouble wrapping around with many worlds interpretation is how I as an observer end up in one of the many bifurcations. Any links you can share that will help me with understanding that is welcome! The Stanford Encyclopedia of Philosophy ( https://plato.stanford.edu/entries/qm-manyworlds/ ) goes into this in some depth, and it seems like the right way to think about it is say that "I" in one bran…

> The part that I have trouble wrapping around with many worlds interpretation is how I as an observer end up in one of the many bifurcations. Pour water down a hill. Water clings to water, and we have hills that already have lots of correlations. We get streams that break up into multiple streams. How did one stream end up where it is? It seems like a good question, but it is circular. The stream is defined by where…

What you said here makes sense. Forgive me, but I have trouble even articulating what it is that I don’t understand correctly.

Maybe what I meant was this: if I perform a quantum experiment where the spin measurement of an electron could be spin up or spin down, the future me would end up in one of two branches: I measure spin up, or I measure spin down. There wouldn’t be any possible world where I measure a superposition of spin up and spin down, because such a a state is going to decohere rapidly. This makes sense. What I’m unable to grasp is that even though the wave function of the universe contains both branches, “I” somehow experience only one of the two branches.

The answer to that I guess if that the two branches are nearly orthogonal they will merrily evolve independent of each other. But somehow “I” only experience only one of them.

Sorry for the rambling. I’m not able to articulate what I don’t understand.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#54

Post by superposeur »

danbruc wrote: post #52

Do I get this right? Wave function collapse due to measurements is not real, the wave function evolves unitarily all the time. But as quantum states get amplified into the macroscopic world, superposition states are somehow amplified asymmetrically which makes it look like wavefunction collapse.

Yes, except for the “asymmetrically” part. In other words, Many Worlds.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#55

Post by gerdesj »

superposeur wrote: post #47
yoyohello13 wrote: post #39

Im fully willing to believe I just don’t “get it” but I took a pretty deep dive into quantum computing and the underlying mechanics and I kind of got the sense (with QC) that nobody really knows what they are talking about. I got this feeling so strongly that stopped studying the topic all together. I’m probably way off base and I’m probably missing some insights that I could get by going to school or something but t…

These debates over the interpretation of Quantum Mechanics (i.e. what ultimately happens when a “measurement” takes place) are important but don’t bear on the effectiveness of quantum computing. Regardless of your favorite interpretation (almost) everyone agrees that quantum computers should work and be able to do things classical computers cannot.

Credo.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#56

Post by Nevermark »

flockonus wrote: post #21
goatlover wrote: post #5

Earlier quoted context omitted.

The article asks the same question in the last part, wondering whether it's just randomly selected. MWI proponents have always argued decoherence leads to the entire world being put into superposition as decoherence just spreads entanglement to the environment. The math never says entanglement destroys superposition beyond a certain point of complexity (many different entangled systems forming the environment). The a…

Random is a very interesting concept. In relation to nature we seem to use "random" as anything we can't or are currently unable to model. To call something random doesn't mean it's impossible to model, in fact all sorts of natural facts seemed random one day before being covered by a model. One very relatable example example is the motion of stars in the the night sky, which seemed random for ages, until the Coperni…

I am not sure why you are being downvoted.

The use of "random" as explanation or characterization in science has certainly spanned everything from "we don't know", to "there is inherent indivisible physical randomness".

And I would agree, in the latter case it is a crutch. A postulate that something gets decided by no mechanisms whatsoever (randomness obeying a distribution still leaves the unexplained "choice").

It is remarkable that people still suggest the latter, when the theory, both in theory and experiment, doesn't require a physical choice at all (even if we experience a choice, that experience is explained without the universe making a choice).

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#57

Post by phacker007 »

kikokikokiko wrote: post #44

To me, the fact that quantum mechanics is intrinsically "random" and unknowable beforehand, is what makes living bearable in this universe as a sentient being. If we, two legged viruses that we are, could reach a level of understanding that could show the universe to be fully deterministic and every future state to be knowable given that you know the current states, then this human condition would be impossible to st…

I knew you were going to say that.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#58

Post by spot5010 »

TheOtherHobbes wrote: post #31
spot5010 wrote: post #9

Earlier quoted context omitted.

The part that I have trouble wrapping around with many worlds interpretation is how I as an observer end up in one of the many bifurcations. Any links you can share that will help me with understanding that is welcome! The Stanford Encyclopedia of Philosophy ( https://plato.stanford.edu/entries/qm-manyworlds/ ) goes into this in some depth, and it seems like the right way to think about it is say that "I" in one bran…

The problem with Many Worlds is that it doesn't place a bound on the number of worlds, so you can't derive the Born Rule from it. That's quite a serious issues. And arguments against that - like Self-Locating Uncertainty, or Zurek's Envariance - look suspiciously circular if you pull them apart. There's also the issue that if you don't have a mechanism that constrains probability, you can't say anything about the com…

There’s papers that “derive” Born’s rule from the many worlds interpretations, e.g. https://arxiv.org/abs/1405.7907

I don’t claim to understand them though. I have tried.

Re: Are the Mysteries of Quantum Mechanics Beginning to Dissolve?

#59

Post by staticassertion »

Nevermark wrote: post #56
flockonus wrote: post #21

Earlier quoted context omitted.

Random is a very interesting concept. In relation to nature we seem to use "random" as anything we can't or are currently unable to model. To call something random doesn't mean it's impossible to model, in fact all sorts of natural facts seemed random one day before being covered by a model. One very relatable example example is the motion of stars in the the night sky, which seemed random for ages, until the Coperni…

I am not sure why you are being downvoted. The use of "random" as explanation or characterization in science has certainly spanned everything from "we don't know", to "there is inherent indivisible physical randomness". And I would agree, in the latter case it is a crutch. A postulate that something gets decided by no mechanisms whatsoever (randomness obeying a distribution still leaves the unexplained "choice"). It…

It is not incomplete to say that something does not require explanation, nor is it saying it's "magic". It is a cost that your model might incur, that's it.

https://arxiv.org/abs/2503.15776

In this paper a plurality of physicists stated that they felt that the initial conditions of the universe are brute facts that warrant no further explanation. This is not "our model doesn't yet account for it", it's "there is no explanation to be given".

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