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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?

#31

Post by TheOtherHobbes »

spot5010 wrote: post #9
Nevermark wrote: post #3

> None of the leading interpretations of quantum theory are very convincing. They ask us to believe, for example, that the world we experience is fundamentally divided from the subatomic realm it’s built from. Or that there is a wild proliferation of parallel universes, or that a mysterious process causes quantumness to spontaneously collapse. Actually, the "many worlds" "interpretation", simply treats the highly suc…

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 common mechanism of any of the worlds you're in. Your world may be some kind of lottery-winning statistical freak world which happens to have very unusual properties, and generalising from them is absolutely misleading.

There's no way of testing that, so you end up with something unfalsifiable.

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

#32

Post by superposeur »

jadbox wrote: post #2

How does "quantum darwinism" effectively select a state? Like how does that work in principle- what is the selection criteria.

It doesn’t. Decoherence is the technical step in the Everett picture defining what a “classical branch” even is and explaining how the state vector branches. Every claim that “Decoherence” somehow offers a distinct interpretation to Everett is pure confusion.

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

#33

Post by Findeton »

artrockalter wrote: post #28

It would be interesting if most of our confusion with quantum mechanics came from treating probabilities as independent when they are actually highly correlated. I don’t really know any physics, but I’m familiar with probability and this type of problem seems to be the most common error in interpreting probabilities.

I wonder how this work relates to Jacob Barandes’s indivisible stochastic processes.

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

#34

Post by butILoveLife »

artrockalter wrote: post #28

It would be interesting if most of our confusion with quantum mechanics came from treating probabilities as independent when they are actually highly correlated. I don’t really know any physics, but I’m familiar with probability and this type of problem seems to be the most common error in interpreting probabilities.

I don't have any skin in the game, but people should be aware of Induction vs Deduction.

Induction had the earth at the center of the solar system and had the best calculations to predict where Mars was. Copernicus said earth was at the center, the equations were simpler, but were worse at predicting the location of planets.(until we figured out they moved in ellipses)

When we say "All swans are white, because I've never seen a black swan." Its probabilistically true. That is induction. If we found swans didn't have the gene to make black feathers, that would be deduction.

Deduction is probably the most true, if it is true. (But it is often 100% wrong)

Induction is always semi true.

Quantum mechanics seems to be in the stage of induction. Particles are like the earth at the center of the solar system. We need a Copernican revolution.

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

#35

Post by Nevermark »

spot5010 wrote: post #9
Nevermark wrote: post #3

> None of the leading interpretations of quantum theory are very convincing. They ask us to believe, for example, that the world we experience is fundamentally divided from the subatomic realm it’s built from. Or that there is a wild proliferation of parallel universes, or that a mysterious process causes quantumness to spontaneously collapse. Actually, the "many worlds" "interpretation", simply treats the highly suc…

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 it is. You are here (in some circumstance), because the version of you in this circumstance is you.

A transporter accident that creates several versions of you, on several planets with difference colors, doesn't need to explain to each version how they ended up at a planet with their color. Even if for a particular copy, it seems like there should be an answer why they showed up on a planet of a particular specific color. The "why" is just, all paths were taken.

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

#36

Post by AnimalMuppet »

A_D_E_P_T wrote: post #17
lukol wrote: post #6

opens coat Hey kid, wanna try some superdeterminism?

The Block Universe Theory, which relativity all but demands, makes that a pretty potent drug!

> which relativity all but demands

Hardly. Some philosophers say that. But I don't take much from philosophers reasoning about physics.

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

#37

Post by Joker_vD »

goatlover wrote: post #5
jadbox wrote: post #2

How does "quantum darwinism" effectively select a state? Like how does that work in principle- what is the selection criteria.

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…

> MWI proponents have always argued decoherence leads to the entire world being put into superposition as decoherence just spreads entanglement to the environment.

Well, duh. It's not like classic objects actually exist, or the classical/quantum divide: everything is quantum, including the "observers". The "classical observer" is a crude approximation that breaks down to a pointy enough question. Just like shorting the perfect battery (with zero internal resistance) with a perfect wire (with zero external resistance) — this scenario is not an approximation of any possible real scenario so it's paradoxicality (infinite current!) is irrelevant.

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

#38

Post by Nevermark »

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…

> 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.

I have no idea what this means.

Is there a bound on anything in reality, in terms of scale? Beyond its own laws?

I am reminded of how often in history, too much time, or too much scale, were unsuccessful arguments against many theories we accept today. Those critiques died without any need for special arguments, because they don't have a logical basis.

Also, there are not a number of many "worlds". That is a reflection of poor naming. There is an interleaving of all interactions, so if you zoom out, a smeared landscape across all configurations, from the plank scale up.

Because the connections involve both intersection (entanglement) and union (alternate paths), we get bifurcation of classical sized paths (dense entanglements), while the individual particles continue unconcerned by how they appear to create different classical histories at large scale.

And yes it is experimentally validated. This is the theory that everyone accepts in the lab, even as larger scales of experiment continue to progress.

But some people have difficulty believing/visualizing that it continues to work at larger scales. Despite no scale limitation in the theory, no scale related violations ever suggested experimentally, and the strong likely that scale limitations would produce new physics in at-scale observations of our cosmos if they did exist.

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

#39

Post by yoyohello13 »

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 that’s was just my experience with the subject.

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

#40

Post by superposeur »

prmph wrote: post #26
Nevermark wrote: post #3

> None of the leading interpretations of quantum theory are very convincing. They ask us to believe, for example, that the world we experience is fundamentally divided from the subatomic realm it’s built from. Or that there is a wild proliferation of parallel universes, or that a mysterious process causes quantumness to spontaneously collapse. Actually, the "many worlds" "interpretation", simply treats the highly suc…

I think the MWI is actually the just-so explanation you claim to avoid. Is it falsifiable? If you have a theory that seems unassailable by any logic, that's a good signal it is tautological and not very useful.

Yes, the MWI is falsifiable. It asserts that objective collapse does not occur, therefore any observation of objective collapse (such as predicted by GRW or Penrose-Diosi) would falsify it.
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